My teacher has trained/visited at an aikido dojo in Vegas on two seperate occasions (he had to attend a conference for work so no vacation for him!
). He said they were a friendly enough group. I don't know how many dojo are there. He said this one presents itself as a Christian based dojo. If you're not a Christian this may or may not offend you. I suggest, as others have mentioned, that you find out where you might want to visit/train (internet search) and contact them.