There's a place about 20 minutes (going the speed limit

) from where I live called Blitz-Krieg Paintball, BKA for short.
Link:
BKA paintball
$15 gets you in for as long as you want.
$15 gets you a bag of 500 rds of paint (not bad quality)
Free unlimited air (CO2 or HPA)
Add an extra $10 if you want/need to use their gear...
Total: Around $30 for 2 hours of fun (i don't use much paint)
For birthdays:
B-Boy/girl gets in free and gets 1 free bag of 500.
Rate for everyone else is $10 to get in and $15 for 500 bag of paint. The cosr off renting gear goes down to $5, too.
Sundays: BYOP
They have 3 or 4 different brands of paint. From the cheap field paint (which doesn't suck) up to Marballizers. They have some AWESOME fields there. 2 woodsball courses and about 10 other airball courses. The refs are fair and are very helpful. They have even hosted some tournaments. I love them and would recommend them to anyone in the area.