I also have oily skin, and have discovered that I can only use powder foundation. Liquid foundation makes my face look like someone threw water on me half way through the day. A great place to go is a place called The Cosmetics Company. You can usually find them at Outlet shopping centers. THey have high end make-up at a significant mark down. If you are looking to stay under $15, I have used Loreal True Match Naturale Mineral powder foundation, and pretty much anything in the Physicians Formula Mineral Wear. I haven't found any Primers that actually reduce the oil production on my face. During the day, I carry a small powder compact and retouch when I'm in the ladies room. The oil absorbing sheets by Clean & Clear work really well too. They absorb face oil, without removing your make-up like tissue does.