i know but im not telling
also you have asked a really vague question, there are a few factors which go into the question your asking.
Type - lots of sites use different varying grades of paintballs from white box paint all the way to proto and stuff like this (I have used proto int he past)
Manufacturer - its the same as above lots of different companies sell at different prices dependong on so many things, like flooding market, offloading old paint etc etc.
Where your buying it from, shop a might do paint x for Y shop b might do paint x for z, etc etc.
Also bulk the more you buy the bigger the discount, a small site who only use say a pallet a month wont have the same buying power as someone who uses 10 pallets a week.
Delivery is also another factor do you want the paint heated or cold on transport.
Best bet is to ring round manufacturers, agents and shops and see what they say.
Jon