What are some good resources for grokking the uses and theories behind DataMining?
Check this tutorial, good for start working with data mining models...
There's an excellent Google Tech Talk called The Statistical Aspects of Data Mining, which I followed. Even bought the book associated with it!
Data mining includes a lot of areas, eg machine learning, algorithms, information retrieval, natural language processing
Here are several books:
IR : http://nlp.stanford.edu/IR-book/information-retrieval-book.html
NLP: http://nlp.stanford.edu/fsnlp/
Machine/Statictical Learning: http://www.amazon.com/Statistical-Learning-Theory-Vladimir-Vapnik/dp/0471030031
Try to google vapnik, chervonenkis, bishop
Neural Nets: http://www.amazon.com/Neural-Networks-Comprehensive-Foundation-2nd/dp/0132733501
Algorithms: http://www.amazon.com/Introduction-Algorithms-Second-Thomas-Cormen/dp/0262032937
And also you may find nice lectures on http://videolectures.net/