Best way to find a mentor i would say is to go to the forum. Yes, you will get most if not all the answers from the experts. There members with a lot of experience who have understood SFI and seriously doing this business.
You can choose one from your upline too, whether it is your sponsor, co-sponsor or team leader, whoever you feel comfortable with. Then ofcourse there are top leaders in SFI, do your survey and choose one to get help.