Guppy's one will be fine. Lots of std trend stuff plus introduces the gmmas.
Look for a book by Nick Radge. He's taken a lot from some older work by Curtis Arnold.
John Hills the ultimate trading guide
Adventures of a Currency Trader is an enjoyable read that relates to trends
Technical Analysis of Stock Trends is cool.
Don't read anything by Mike Covell --- derivative rubbish.
Curtis Faith is more interesting and more real if you are interested in turtle trend trading.