Someone needs to publish an official price guide. Comics have them annually, so do sports trading cards, gaming cards, action figures, and even HeroClix.
There was one published back in 2007, and I have it. But it's pretty dang bare-bones. Just pure text on paper (and obviously woefully out-of-date at this point). I wish someone would make one, annually, and would do it justice like the Overstreet Comic Book Price Guide which is chock-full of stats, grading tips, pics, and historical guidelines.
Here's a pic of that 2007 price guide, it's here in the database:
http://vgcollect.com/item/36222
Price fluctuates too much. It wouldn't work. Besides, who prints stuff anymore?
Which is why it would have to be printed annually. And it works fine for things like comics and trading cards. All price guides are general guidelines anyways, not precise, of course spikes and whatnot happen. (Which is what market-reports for the past year cover in the good price-guides like Overstreet.) I can't tell you how useful of resource and source of information Overstreet Price Guides are for comic collecting.
Honestly, I think it works in comics and doesn't fluctuate much because almost every comic collector uses that. Because of its widespread use, it is authoritative. Its a catch 22. The price guide would have to be widely used to be accurate. However, the guide would have to be accurate to be widely used. Comics just had the privilege of being pre internet boom. People used Wizard primarily.
Comics fluctuate just as much as games, probably more actually. Spider-Man 2099 #1, for example, rocketed-up in price when the initial announcement of his new ongoing happened, then just as quickly fell again.
A Gwen Stacy Spider-Man book that was just released for $4 last month, is already going for $30-$40.
Like I said, though, price guides are just general guidelines, not exact pricing. Doesn't mean their useless at all. It gives you a general idea. And besides the prices, is a fantastic resource for stats, dates, and facts on stuff.
It seems the general consensus with game collectors, though, is that resellers are evil. And if you need guide, you must be an evil reseller. But I had a price guide as a kid, for my comics. It's fun to satisfy curiosity and flip through even, even if you don't use it as a resource for info.
