I was really lucky to find my group. I started with a parks and rec group here in town and was hooked from day one. Then I did a little research for classes around me and found that my ballet teacher (Who I took dance from when I was 5!) was teaching belly dance. I have been with her ever since.
I can totally relate to your feelings about walking into a room of Kardashians. I was terrified walking into my first class... but after 3 years of doing it, I can tell you this... Belly dance isn't about size and shape.. it's about passion and spirit. Sure, there are girls that I dance with that are smaller than me and move differently than I do.. but at the same time, there are some moves that I, as a bigger girl can do better than others. Ya gotta have hips and a belly to do it.
One of my favorite local dancers is a bigger girl, and let me tell you.. when she is on stage.. she owns it. She is probably one of the most graceful people I have ever known and is a huge inspiration to me because she isn't afraid to go out in a bra and skirt..
If you want, Send me a PM and I will send you some links to some youtube videos that may just help calm your fears.