I'd be buying sauces and seasonings. And different kinds of chips. To be honest, after living here three years, I really enjoy Korean food and rarely miss anything from the US. That being said, when I go back to visit, the grocery store is both awesome and overwhelming. Also, the proliferation of these foreign food stores selling EVERYTHING means that only the truly unique, niche American stuff is left back at home.

In my old town, a suburb one hour south, I can go by Flinstone Gummies, blue cheese dressing, Fun Dip, Tums and ranch seasoning. Obscure, but it's there.

A lot of people also use iherb.com