All of the leagues of Rugby Union in the United States are governed by USARugby.
The west side of North Dakota is a little far from the other teams, but not unreasonably so. I would suggest forming a social side for western North Dakota and practice with the intent of going to a few tournaments. (
Maggotfest is a huge one, and isn't too far away)
You should be able to schedule some friendly matches between teams within driving distance.
Go to the USARugby site and "Find a Club." You can search by state and find the closest ones. Contact those teams ASAP. They should be able to help you find the good tournaments and get you connected to the Union people who can help you out. Also check out the teams through:
http://www.maggots.org/MRU.htm
http://www.minnesotarugby.org/template.php?sid=25
http://www.greatplainsrugby.com/template.php?sid=61
http://www.greatplainsrugby.com/template.php?sid=59
I'd also contact the Canadian clubs that are close. You can find them through:
http://www.saskrugby.com/
http://www.rugbymanitoba.com/league.php?sc...gueInfoID=28162
For tips on starting a rugby team, check out:
http://www.texasrugbyunion.com/template.php?sid=63 (scroll down to Starting a College Rugby Club)
http://www.usarugby.org/media/EDocs/StartUpKit1.pdf
While those are aimed at college teams, there is still a ton of good info. If you can find a football field to play on, you can use those uprights. If not, you can use PVC to build them. To start out, you can have each player purchase their own jerseys. This worked very well at one of my teams. You pick a cheap jersey, and can get a logo put on if you wish, but you don't need to. Say everyone needs a solid grey jersey. They can buy it themselves, or you can order them as a team and get a volume discount. You might even be able to buy an old set from one of the nearby teams.