You can order Tracking: A blueprint for learning how from
www.pathways-press.com
Another book title that hasn't been mentioned yet is The Complete Guide to Tracking by Bob Carss
There are a lot of books on tracking when you start to look for them. Some very good, some very bad. Some are very general in their content others specialise in one aspect of tracking eg feathers or skulls. I would reccommend getting one or two general tracking books and then look at some of the more specialised books.
I just tried to come up with a list of the 3 books I wouldn't do without and its very hard. All the books mentioned so far have their merits (and their faults).
I would go for
i) Hamlyn guide to Animals, tracks, trails & signs
ii) Tactical, Tracking Operations
iii) either Tom Brown's Nature Observation and Tracking or The Complete guide to tracking by Bob Carss
Yes I know that's 4 but tough! Ask me this again in a few months and I would probably come up with a different list
Tracking can be a very personal thing. A style of tracking may appeal to one person and yet be hated by another. Some tracking styles are based on military training, some from a Search and Rescue outlook, some are very spiritual and some aimed more at the naturalist. I suggest that you go to your local library and see what they have got there. If there aren't any books on tracking put in a request to order one of the titles mentioned. That way you can see whether you like the content before you buy it.
Good luck!