If you have good to perfect skin, then I would definitely not wear foundation. I have been wearing makeup for years and I am a makeup addict. I have always had very good skin, but when I was younger I actually did wear foundation. I don't anymore, and it looks so much better. Foundation evens out your skin tone and can hide imperfections, but if you don't need it then don't use it. I would suggest using a concealer for under your eyes and possibly the crease of your nose or any other red spots, but I wouldn't buy a foundation. My beauty routine for my face consists of a good skin care regimen: washing, tone, and moisturizing twice every day. Make sure you do that and your skin will be kept clear. For face makeup I use: concealer for underneath my eyes, powder, bronzer, highlighter/illuminator, and blush. If you use these, your face will look much more natural then if you apply a foundation under it. And if you absolutely insist on using a foundation, ONLY use one with sheer coverage or even use a tinted moisturizer. My favorite place to shop for all of my makeup needs is Sephora. If you haven't heard of it, then I would stop by a store if you live near one or go to Sephora.com. They have a very wide range of products, great costumer service, and are just a great company in general!
Here is a link to view some products for your face on Sephora:
http://www.sephora.com/browse/section.jhtml?categoryId=C108
Just look on the left hand side and you will see all of the different categories you can choose from. Browse through their website and find something you like!
Hope this helps and take my advice: you are lucky to have good skin, so foundation is really not necessary for it =)