Try Expert Card Technique by Hugard & Braue. Anything by Marlo is great in my opinion! Marlo does some difficult moves, but you must be stretched if you want to grow in your card magic. -- Cardician66
Funny you should give this advice, because this is the very course I took.
When I first became interested in card magic ECT was the first book I bought because it was at the book store.
And the best and only card magician I knew at the time gave the same Marlo advice.
Both were completely terrible entrees into card magic, because they rely on a host of previous knowledge, and are rife with jargon and terse prose. Only years later do I find myself both conversant and capable of digesting the information and ideas contained in ECT and much of the Marlo oeuvre. These are volumes for experts, not "your favorite books to get a beginner 'thinking,'" which was Darren Roberts's question.
Rereading my previous post, I must say I didn't intend to recommend ECT to the beginner, but I was pointing out the strong value contained therein.
I would recommend Carneycopia
simply because it seems like they should be read in that order.