I have recently learned about two books that cover lowball:
Pot-Limit and No-Limit Poker by Stewart Reuben and Bob Ciaffone has a London Lowball section.
Precentage Hold'em and the Lowball Book by Justin Case.
I haven't seen either of these but would appreciate hearing from anyone who's read them. (And I'd appreciate a review on the
Lowball Wiki even more!)