Spanish Translation Tools
For synonyms and antonyms:
Great Ways to Learn Spanish Online
BBC Languages: Spanish--A comprehensive and lively collection of free audio and video courses for both beginners and intermediate learners.
About.com Spanish Language -- The website maintaned by About.com's Spanish Guide features a variety of language lessons, blog posts and several interactive elements including quizzes.
Spanish Blog: Language and Culture -- Great blog maintained by Transparent Language, a leader in language software. It has a staff of several writers and uses lessons, videos and even cultural anecdotes to help you learn grammar, vocabulary, pronunciation and more.
Coffeebreak Spanish--Excellent Spanish Podcast aimed primarily at beginning and early intermediate learners.
More Online Resources
Notes in Spanish and Notes From Spain --Sister sites that offer a wide variety of helpful resources for Spanish language and culture. NIS focuses on learning the Spanish language with a series of podcasts and NFS focuses cuisine, lifestyle and travel in Spain.
The Spanish Blog --A good resource put together by a Spanish teacher from Bilbao, Spain. Blog posts range from pronunciation guides to recipes and there are a wide variety of cultural and multimedia resources to help you learn and have fun at the same time.
Spanish Language and Culture--Maintained by a Spanish professor at Colby College, this website contains grammar exercises and some excellent activities which use songs, videos and even poems to help improve your Spanish.
FSI Language Courses--Free Spanish audio courses designed by the U.S. Foreign Service Institute. As such, it looks a bit stiff and formal but there are exercises, lessons and a wealth of audio files.
Learn Spanish in Chile--Their Spanish Learning Area offers online quizes and games for practicing Spanish.
Study Spanish.com-- Features a wealth of tutorials for grammar, pronunciation, vocabulary and verbs available for free. Mostly for beginners and intermediate learners, with advanced lessons available if you sign up for their premium account.
Social Sites to Help Learn Spanish
Bitacoras and Meneame--If you've heard of the social bookmarking site Digg, these are two Spanish language equivalents. Search across thousands of blog posts and articles in Spanish, read the most popular posts on their homepage and vote for ones that you like. Great way to practice your reading skills and you might even meet some interesting new people. The two function almost exactly the same.
Tomisimo.org Forums and Wordreference.com Forums--Active language forums where you can post grammar questions to have them answered by native speakers, or you can learn by reading other threads or answering others yourself. You will almost always get replies by authoritative, knowledgable posters, which you can verify by seeing their native language, number of posts and reputation.