Welcome Rwolf, I'm a newbie as well!!! I found this site very informative and a great asset. I race off-road cars in Baja so my trucks are SRW, they get very overloaded on raceday for 16" wheels and load rating "E" tires. I'm looking to convert to 19'5" wheels to carry the load.
Anyway, I'm not sure if you're looking to stay with the stock tire/wheel size, but I've been doing alot of research on this subject and here's what I've found....
Wheels:
www.ricksontruck.com - this company makes 19.5" wheels for american trucks
www.stocktonwheel.com - this company can make any kind of wheel you can think of. Check this site for an example:
www.turtleexpedition.com - go to "vehicles" then "Turtle V" it's an F-550 with single rear wheels. These are 20's, they can also make 22.5"
www.earthroamer.com - this f-550 has SRW with 22.5" wheels.
http://www.usa6x6.com/ - this site has "super singles"
Tires:
BFG makes a 16" 285 E rating
Toyo tire makes a 17" / E rating in both a 35" and 37" tire
Rickson truck has a bunch of tires on their website for 19.5" wheels
Michelin makes "super singles" in 20" and 22.5" wheels
Hopefully this will get you started. Let me know what you think
James