I like Smashbox Photo Finish Light primer (it's oil-free). It doesn't dry my skin at all, and really seems to help my makeup stay on longer. I got the 2 ounce jumbo size from
Sephora, and I still have a ton of it left...a little really does go a long way.
I also like Urban Decay De-Slick In A Tube for touch-ups during the day. I just take a little bit of it and pat it on over my makeup when oil starts to break through. It doesn't disturb your makeup, and instantly makes shiny areas matte again. It can be used as a primer as well, but the tube is rather small so I don't use it for primer.
I did NOT like Makeup Forever's All Mat primer...it has some kind of silica in it, and apparently it and my oily areas did not get along, and it kind of made my face feel greasy.