What is the procedure for buying a fifth wheel?

http://www.theautochannel.com/news/2002/11/03/149912.html

We have a 2003 Duramax diesel 3/4 ton and a 36' 5th wheel @13,000lbs. Dry I was reading all this and thinking Wow I dont have enough truck to pull my 5th wheel, that I have been towing for 5 years! I pulled up the link and chevy 3/4 looks to be rated at 16,000lbs for a 5th wheel. The motors are all the same in 3/4 and 1 ton trucks That being said we are looking to get a 1-ton diesel dually. Mostly because we Tow livestock and tractors also.