Other GRE sites
Hapax Legomena -- This is one of the few GRE sites out there. This site has great links, and includes a study guide that is well worth checking out, especially since it covers a number of things that mine does not.
Litgeek -- This is a blog site that has pod casts of study material by theme. If you are someone who makes a commute or is an auditory learner, these pod casts are great.
A Recommended Reading List for the GRE -- Remember, you don't really need to read all this stuff, but you should have studied everything on this list if you want to ace the exam. This list is somewhat different from the ones included in the study books, and nicely complements their lists.
A livejournal community for the GRE in Lit -- I don't know how heavily trafficked this site is, but it's a good place to ask questions. Another community, called "Who Got In," is pretty much grad school crack. If you want to see how some folks got into the very best schools, browse through some of these conversations.
Reed College has a nice site here. This site seems to be incomplete, but the site is very similar to this one in that it provides relevant background info, plot synopses, terms -- just what's relevant to the exam.
Greatauditobooks -- A site that "contains a collection of free audio books that are most likely to appear on the GRE Subject Test in Literature." How's that for convenience?
Poets Grave has a ton of definitions of poetic terms, and may come in handy when you encounter one you don't immediately recognize. It also references important poems.
Note that there are few practice tests out there, so it's worth studying a whole lot before you do a diagnostic exam since you won't get to do too many of them.
ETS will give you one for free when you register. It's available here.
And here 's an exam from 1994 that's pretty good.
A few other websites and resources worth exploring:
Mobile Mecum: Thanks to the hardwork of Ahuva Goldstand, you can now enjoy Vade Mecum on the go. All the contents of the Vade Mecum (and then some) in a single, reliable Word document. Enjoy!
Luminarium is a good place for info on early British artists. It's pretty comprehensive.
Wikipedia -- They have pretty much everything. When in doubt, check wikipedia.
Bitter Laughter -- This is my blog. It's an excellent place to spend a little time away from Vade Mecum.
Gerry Canavan -- This is another great blog. It belongs to my friend Gerry, a PhD student in Duke's Literature Department.