If you have been considering learning Python and are confused about how and where to start, there are several good suggestions that have recently been posted over at BlenderArtists.org.
Lots of people have posted links to good Python resources, but a good core of resources was in Friday13's post:
-How to Think Like a Computer Scientist: Learning With Python: Great book, available in both printed and free downloadable version.
-A Byte of Python: This is the first one I read. Though still in progress (it was recently ported to Wiki so others could contribute), it already offers a great deal of information, and it's easy to understand, even for those who've never coded before.
-Dive Into Python: For experienced programmers only, but it's downloadable so you might want to keep this site bookmarked until you're ready to read this book.
-Non-Programmers Tutorial For Python: A fairly good amount of content, and a bit outdated (though it's now in Wikibooks, so it's bound to change and evolve). Also good for people who've never programmed anything (as the title suggests).
-Python.org: Documentation Index: Links to all the good sites (above links are included here).
-Python Tutorial: Essential, but not really aimed at non-programmers. I recommend reading it after gaining some experience, for learning things you might have missed.
Of course there is also more Blender specific instruction in terms of Blender such as Stephen Swaney's BSoD project Introduction to Python Scripting and the BlenderPython API introduction. There is also BlenderPython.org (which we've posted about) and as the name implies, there's a wealth of information regarding using Python for Blender.