I order all my GF supplies from Midwest
and the shipping isn't bad at all. If you want rice extract, you can either use gluten free brown rice syrup- usually available at health food stores, or Midwest carries rice syrup solids which are the same thing and the brand they carry is gluten free. IMO ordering a kit isn't worth the trouble and it costs more, you're better off making your own recipe and getting everything you can online or locally...Austin Homebrew Supply also carries sorghum syrup.
If you want to malt sorghum, theres a link somewhere around here that you can get a 5 gallon bucket pretty cheap and the shipping is really low (check my malting gf grains thread). But the whole malting process itself is a pain if you don't have spare time.