I'm kicking around the idea of getting bigger wheels. Right now I've got stock 17" wheels on my 2007 Suburban. Looking at 20's, but not really looking for that lowered tuner car look, just want more meat under there. Truck is pretty much blacked out so I might go with black wheels, I don't know. Show me!

 

You may want to use the Tire Rack application that allows you to view rims on your truck. It will give you some ideas. Often they will have a number of different sizes to view for each product, ie. 17", 18", 20", 22" etc. You can change the color of the vehicle to match what you drive. Overall, it is a good tool to help visualize something.

Wheels for 2007 Chevrolet Suburban 1500

Also, if you do a quick google image search, you will see lots of ideas.