Refdesk - comprehensive "fact checker for the internet" - instant connection with every reference site imaginable. Sign up for their reference site of the day. If you had to pick one mother-of-all-reference sites, this is it.
iTools - Slick, elegant multireference site that provides links to all kinds of internet "tools": Search tools (search engines, web directories, newsgroups, video), Language tools (dictionaries, terminology, theasauruses, crossword solvers), Research Tools (Encyclopedias, newspapers & magazines, biographies, quotations), Financial tools (currency converter), Map tools (maps, driving directions), Internet tools (web, network, html tools), People Search Tools (address & phone, lookup by phone number, email address, international).
SurveyMonkey - create your own online survey
50 Mind--Mapping Tools for College Students - online programs to help you organize, outline, and think more clearly
German-English Dictionary - now you have no excuse for not knowing what Strauss, Mahler, and Hindemith are telling you about how to play their music.
French-English Dictionary - ditto for the French composers
OneLook Dictionary - Your choice of searches for English definitions, reverse dictionary, or translations. Useful list of search examples, e.g. using blue* to find words and phrases that begin with blue, or bl????rd to find words that start with bl, end with rd, and have 4 other letters in between, and other wildcard searches. List (with links) of 116 general dictionaries and glossaries, plus other lists of specialized dictionaries in Art, Business, Computing, Medicine, Miscellaneous, Religion, Science, Slang, Sports, Technology. Slick.
Babelfish - quick translation of almost any language
Google Translate - translate text, web page, or document
Giga Alert - tracks items you're interested on the web
Language Learning Library - free online language learning resources: grammar, common phrases, nouns, numbers, telling time, alphabet, dictionaries, cultural information.
WorldCat - "The world's largest network of library content and services." Lets you search the collections of libraries locally and around the world (10,000!). Find books, music, videos, research articles, audiobooks and other digital articles; you can review items or contribute facts. Create your own free account, lists of items you'd like to track or share with others, build bibliographies, get plug-ins for Foxfire or Facebook, even try some "planned serendipity."
Library of Congress Research Tools - includes links to the L.o.C. Online Catalog, Prints & Photos, SONIC (database about the LoC's 78 rpm & 45 rpm phonograph disks), access to over 300 other library online catalogs, thesauri, LoC primary source finding aids, and more.
Bookwire - find libraries around the world, plus many links, e.g. book reviews, Publisher's Weekly, book in print, many more.
Arts & Letters Daily - Not a reference site per se, but a terrific sampler of fascinating current articles from all over the web on many, many subjects.
Biblioscape - "ultimate librarian's reference" - including bibliographic database (Library of Congress, library catalogs, Fed. news service, ElectricLibrary), Libraries on the web, Library Reference Center, Repository of Primary Sources, Libweb, University home pages, online encyclopedias, desktop reference, research funding, (GrantsWeb, etc.), financial aid, academic organizations, and much more.
Internet Public Library
Internet Reference Shelf - web resources compiled by the Library of Congress
Internet Archive - "a digital library of internet sites and other cultural artifacts in digital form." Text Archive is here. Check out their movie library - free movies, films & videos.
Librarians' Internet Index - "Websites you can trust" - links galore. Music subheading; sub-subheadings: Classical Music,
New York Public Library - Gateway to vast resources of every kind.
Libweb - library servers via the www. 7900+ pages from libraries in 146 countries.
Libdex - directory of libraries around the world
Library Catalogs Worldwide - Links to library catalogs around the world, by Yale University
National Library Catalogues Worldwide
Center for Research Libraries - consortium of North American universities, colleges and independent research libraries. The consortium acquires and preserves newspapers, journals, documents, archives and other traditional and digital resources for research and teaching. These resources are then made available to member institutions cooperatively, through interlibrary loan and electronic delivery. Includes special collection databases (US ethnic newspapers, foreign doctoral dissertations, etc.)
The European Library - "search the content of European national libraries"
LibrarySpot - Online reference site of vast scope. A sampling of their links: Online libraries (of every sort), news, magazines, podcasts, poetry, speeches, almanacs, associations, Ask an Expert, biographies, countries, current events, dictionaries, encyclopedias, grammar, people, public records, how to, quotations, statistics, white pages, maps, zip codes and a whole lot more.
Ready, Net, Go! - index of archival indexes
Scholarpedia - like Wikipedia, except that articles are peer-reviewed and written by scholars.
Sources and Experts - created for journalists to make it easier to find experts on all kinds of things.
Intute - "Helping you find the best websites for study and research." This link goes directly to the Creative and Performing Arts section.
Virtual Reference Desk - here's their Music page.
Soyouwanna - "teaches you how to do all the things nobody taught you in school"
eHow - "How to do just about everything"
Answerbag - ask a question about anything, or be an expert and answer the question of others in our specialty.
Infoplease - Almanacs, atlas, encyclopedia, dictionary, thesaurus, features, quizzes, timelines, news, history, sports, biography, links, and much much more.
Wikipedia - everyone knows about Wikipedia. Right?
Delicious - "social bookmarking" site; "biggest colleciton of bookmarks in the universe". Word of mouth on what's popular, interesting, and fun.
Digg - similar to delicious.com, with perhaps a bit more emphasis on technology. Don't look at either of these if you have work to do. But if you're all done...
CutePDF - create PDF files; add, delete, rotate, resize, reorder pages; add stamps, overlays, headers, footers. Windows only.
Google is not only everyone's 1st choice search engine, but it offers a host of other features for the web-wise, including:
Images, Videos, Email (Gmail), Calendar (if you have a gmail account - same for the following items), Documents (create, share spread sheets or text docs), photos (store, share photos), Reader (subscribe to blogs, follow people who share publicly), Sites (create/share your own web site for free), blog search, Book Search (search full text of books), Scholar (search scholarly papers), Blogger (create your own blog for free), Groups (create your own mailing list/discussion group), YouTube, and more. Google also offers a "Custom Search Engines" (CSE) that search within certain topics (Arts, Bloggers, Business, Computers, Educators, etc.).
To be a power Google user, see Google Search Shortcuts cheat sheet.
Non-Google Search Engines:
Exalead - Google competition; it has a thumbnail of the website image along with the suggested link. It has a few beyond-Google bells and whistles: a column on the right side gives the site type, multimedia, file type, a list of related terms, languages the links appear in, and country where the links originate. If you click on a country, it will show only results from that country. Nice.
Clusty - Not only lists links, but puts results into "clusters" of related topics so that you can review related links together.
Bing - Microsoft's new competition for Google. Attractive layout.
Yahoo Search - the look is very Google.... Caveat: Ask intersperses sponsors with search results
Ask - ditto, but so does everyone...
Education World - search engine for education +lots of resources, references, and article archive
Picsearch - image search engine
Dogpile - is a meta-search engine that collects the results of several search engines
Jux2 - another meta search engine that compares results from Google, Yahoo and MSN in one search
Infomine - "Scholarly Internet Resource Collections"
Hakia - a "general purpose semantic search engine" focused on quality of web site, not popularity. A search for "French horn" instanlty yielded a number of results, all classified under categories: Origin of the instrument, How to Buy, Images, Famous Brands, Lessons and Videos, Find a Job/Gig, Photographs and Pictures, Parts & Accessories, and more.
Cuil - Cuil is the Irish word for knowledge. Searches are based on content and relevance, not popularity (a shot at Google...), analyzing the web rather than users. Cuil claims to search 3X more web pages than Google.
SearchMe - lets you search within a category, so that, for instance, a search for "horn" doesn't turn up mountain goats.
Twine - "Discover information that matters to you. Collect and share bookmarks and other content. Receive recommendations based on your interests."
Wolfram Alpha - for anything remotely to do with computation, conversion, calculation, or computation, this is the new 10 ton gorilla in town.
Kosmix - what's happening on the web right now.
Wikia - "find and collaborate with people who love what you love."