Grammar Practice

Barbara Nelson's Webpage (exercises to practice a variety of grammar topics)

Study Spanish (grammatical explanations and lots of rote practice, including audio)

Grammar Notes (grammatical explanations and practice)

Dictionaries

Word Reference  (forums, Spanish to English, English to Spanish)

Real Academia Española  (official Spanish dictionary)

Interesting Blogs

http://technologyenespanol.blogspot.com  (my personal blog from my class on technology)

http://www.notesfromspain.com/ (blog about life in Spain)

http://livinginpatagonia.com/ (blog about learning Spanish in Argentina)