Raptorman, I am still tinkering with my first efforts at a motor conversion. Personally I have found this far more rewarding than buying something off the net, learnt a lot in the process to. There are some pictures in my files you may find interesting?
I do not know enough to attempt building my own from scratch, nor do I have the need. I like the smaller mills that I can get to charge my 12v batteries then put that charge to use, it is at my current (limited) level of understanding. Lots of reading on here on motor conversions, I would suggest looking for "Jerry's" posts, personally I have found them to be a wealth of information - even if I don't (yet) understand it all!!
Good luck.