Chris Jericho could write one. When he winds down from wrestling, he can make a heap on money for his family, while sitting at home. It would probably be the easiest way for him to make some moolah, save for a Chris Jericho DVD box-set. Plus the guy is great with words, and he could make me mark out on every page if it was flooded with old "Jerichoisms".
Kane writing one wood be genius. If they could arrange it to be in character (they already have a biography, but an autobiogrpahy would be nice) it would be good, but if Glen Jacobs comes clean in an autobiography and cuts loose his frustrations, it would be magic. I don't mean to pressume anything about Glen Jabocs, but I think he has qualifications to be an English teacher. This paired with the fact he must have some frustration with his character being chopped and changed regularly, and him being left out of the loop when he's been one of the more consistantly over and threatening characters in WWE history, he could write a pretty darn good book, if he hasn't started already. Writings a fantastic way to express yourself and get rid of built-up feelings, so it wouldn't surprise me if "Kane" has already scribbled some notes down somewhere to relieve some tension.
Those are the main ones from me, although Rey Mysterio could have some interesting stories to tell, and The Big Show is a genuinely enertaining guy. I might even be coerced into buying a Chistian autobiography as well.
I don't know if I mean this seriously or not, but Val Venis has been in the business for a while, and could share some good stories and experiences. "Sean Morely Treated Poorly: A Look From the Lower-Card"...