If you're talking about repairing cracks in the original wheel yourself, PC-7 epoxy works well. They have a short description on their website:
http://www.pcepoxy.com/blog/can-you-...x-yes-you-can/ You still have to repaint the wheel afterwards but it holds up well, I did a steering wheel in my pickup 15 years ago and it still looks good.
You should be able to find PC-7 at your local hardware store, I think Ace hardware carries it.