I need a tank, perferably 2004 on but i could probably work with anything else. Looking for one with very little damage, since I'm going to repaint it i don't really care what color it is, unless its black, then that would be perfect. Send me what you have! I'll be more than willing to check it out. Thanks
mlutz9004 has one with some light damage on ebay, starting bid $99. Just search for GS500 gas tank.
Also search for GS500 FUEL tank as in:
GS500 tank (fuel, gas,petrol)
http://cgi.ebay.com/ebaymotors/08-Suzuki-GS500-500-FUEL-GAS-PETRO-TANK-/190582951590?pt=Motorcycles_Parts_Accessories&hash=item2c5fa10ea6
There are a couple nice ones for $250 or so