Well there is Pev's Paintball park. It has something like 40 acres and 14 fields. It even has a small town setup with around 20 buildings. they have food (Pizza, Cookies, etc..) As far as pricing goes I really cant remember but their site is pevs.com - Paintball Super Store
Most of the good fields are out past Manassas. As the previous poster said, Pev's is by far the best. You can drop by or bring a group. It is usually busy on the weekends.