I don't have the book with me at the moment, but I believe it is "Biker Trials" by Paul Cherry that details the links. It has a free preview on google books so if you Google the name Sandra Antelo and/or Guy Lepage it will turn up relevebt information. The Nomads were initially going through Antelo(the daughter of a drug lord) in the early 90s, then later going direct to Colombia themselves.