[Crowdsourcing] RPG Book Buying Guide?

[lightcastle]

Do any of my more knowledgeable friends know if there is something equivalent to the Comic Book Buyer's Guide for old RPG books? As I have been working my way through the old boxes in the family basement, I have unearthed the majority of my old gaming stuff. While I would like to start up some RPGing again in the future, the vast majority of what is here I will never use. Most of it is probably worth the couple of bucks I would get for it at my FLGS, but some of it may be worth more. Is there a central source I could use as a quick check to at least make a first-pass effort and which are worth a second look? Anyone know?