Sorry no one has gotten back to you yet. Must have been a busy weekend for some of the regulars. There is a lot of good information available here for the new comer to this hobby. Here's a link you might find interesting. http://motorbicycling.com/f4/kit-best-1764.html
One of the decisions you'll need to make is if you want to go with a 2 cycle engine or a 4cycle. Each has its advantages and disadvantages. You'll need to do some reading and decide for yourself on that issue. Don't get in a hurry to order a kit; read a lot first before you spend your $. Always feel free to ask questions here before making a purchase or if you have problems with the kit you decide on. Good luck, have fun.