Links
Research
These can be used for more than writing fantasy, but fantasy is what I do, so my list of links is tailored to what has helped me.
The Art of Travel - This site, actually the text of a nineteenth-century book, describes the process of traveling in wild areas. It describes methods of travel that can easily be adapted for different eras and circumstances.
Behind the Name - This easy-to-use database of first names and their meanings is great for naming characters.
International Colored Gemstone Association - In fantasy, somehow, gems tend to come up. (Maybe that's why they call it "fantasy"?) This site helps choose the right rock for the job.
The Language Construction Kit - If you're creating a new language - well, congratulations on being hardcore. This site has some great tips and things to think about.
Writing Resources
AgentQuery - Provides information about numerous literary agents.
Duotrope - A great search engine for writing markets. If you're looking to sell a short story or poem, check here.
James River Writers - This is a great group, especially if you live around Richmond. It's worth checking out for the annual conference alone.
Preditors & Editors - Numerous editors, authors, and agents have recommended this site to all beginning writers. It can help you make sure anyone you're dealing with is on the up-and-up.
The Rejectionist - If you want a slightly different perspective from Nathan Bransford's, a perspective with more hilarious snark and more heavy metal, The Rejectionist is an agent's assistant who blogs about writing, queries, and more.
Miscellaneous
David L. Robbins: The Official Web Site - I took an excellent two Advanced Fiction classes from Professor Robbins at the College of William & Mary. The man also set up the fantastic James River Writers group and is now working on a literary journal with Richmond public school kids. I can think of no one who gives back quite like him.
Diana Wynne Jones Official Website - The site of my personal favorite author. If you like science fiction and/or fantasy, I cannot recommend her enough.