Wheel width is going to depend on the width of the tires you pick. So go tire pricing first, and find something reasonable, see what width is recommended.
Wheel pattern is 5 x 5.5" Same as some Fords, some older Jeeps, International Scout, and some others.
Metric sized 235/75 x 15 works out to be about 29 inches and is available in many different brands in both AT and MT. I had 2 sets that size (one AT, one MT) on my Samurai when I first started off-roading it. It also fit on the stock rims. So you might look for different Sidekick wheels.
You can follow this link to Southern Four Wheel Drive Association. http://www.sfwda.org/
They have 17 clubs listed for TN http://www.sfwda.org/clubs.html#TN
You might be able to find people in your area that will help you with your project and show you legal places to off-road. They would probably know people in your area that could help with the roll cage to.
As far as Rocky Road goes, I've had good experiences with them (bought twice from them.) Now, I wouldn't rely on them if I needed something within the next 3 days, as that seems to be the biggest beef. They do seem to take a while on some parts.