If you are already using a good moisturizer, you won't need a primer before the moisturizer. You usually use a primer prior to applying make-up. The purpose of the primer is to act as a palette/background for your make-up to stay on you. A primer is usually a hint of moisturizer with a film former.
I say this because most good moisturizer should have a built-in film former for feel aesthetics already.
I use Smashbox primer. You can find it at Sephora. I have areas of redness so I use the green tinted one. It does seem to help the redness and my make up goes on like velvet once the primer is on!! Primer is such a great product.