As far as I am aware, there are not many dojo in Las Vegas. I was there a couple of weeks ago and visited this one:
They were extremely hospitable and welcoming, and the training was very good. They have a nice, clean dojo as well.
I emailed them the week before at the address listed on their website, and they replied with a confirmation of their schedule and location. You might mention in your email how long you have been training and with which organization and teacher, and I am sure that they would be very welcoming.