It's hard to do better than Mark Pilgrim's Dive Into Python. The book is freely available to read on the web, but you can also purchase a hard copy through major retailers like Amazon.
Note that Python still maintains two major versions: 2.x and 3.x, and there are different versions of the book for each:
You might do well to watch this 10-minute overview by Wes McKinney, the originator of Pandas. The video isn't comprehensive, but it will give you a taste of some common operations in Pandas
I would highly recommend Hadley Wickham's book. The pricetag is steep, though, so if possible, check whether your local library has it.