There's really good books on Data Mining at Borders, and a recent bunch of "collective intelligence" books; the Manning books are excellent, but you have know java; you probably also want to install Weka and R, look at the Python suite (numpy, scipy, matplotlib), tools like that; also look up the ~107 (!) algorithms that Bellkor used for Netflix comp.
Strong upvote on that book list. If you want to learn from scratch, start with the "Programming Collective Intelligence" book, then move to "Collective intelligence in action", they're both quite good.
If you've covered and understand the material in both, you're probably ready to consider moving to some of the more academic texts.
http://www.research.att.com/~volinsky/netflix/
http://www.amazon.com/Programming-Collective-Intelligence-Bu...
http://www.amazon.com/Collective-Intelligence-Action-Satnam-...
http://www.amazon.com/Algorithms-Intelligent-Web-Haralambos-...