Okay, so I don't really do cakes very often just the occasional birthday cake for family. When I do it is usually a character pan. I am tired of these and want to make a tiered cake for my son's birthday cake. I have 8" and 6" X 2" round pans. If I am double stacking and torting each layer, how many people will this feed? I am expecting at least 30-40 people of various ages. I have no idea if this will be enough or way to much Please help!!!

I triple stack and serve 25-30 at the very most from a 6x8. And that is for wedding cake size slices.
If you double stack, maybe you can make 1 more of the 6" double layers for each of the sides.
Just my opinion.

Here's the link to a chart showing the number of servings for different size/shape pans: http://www.cakecentral.com/article14-Cake-Baking-Cutting--Serving-Guide---2-in-Deep-Pans.html

A 6" and 8" cake will serve 12+24, if serving pieces are 1.5" x 2".