depends on the bike, ie, SV650 will use less tire than GSXR1000. I race a 600 and usually get 4-6 races out of 208GP-As (depends on track and number of laps). I often save them though and use them for a track day after. So, if you race 2 races per weekend, should be able to get 2 weekend out of a set of tires. If you race 8 races in a weekend, you're going through closer to a set a day. I'm sure this varies alot based on track, bike, rider, and how competitive you want to be.
If you're only racing 2 races a weekend, I'll look for race takeoffs -- tires that a really fast guy is used for 1 race/qualifying.
