Internet Programming with Python (Watters, van Rossum, Ahlstrom; MIS Press): this one I personally own. Though it is slightly outdated, covering Python 1.4, most of the information is still relevant and useful. Provides a good tutorial on Python and lots of sample code for Internet applications. One of the co-authors is Guido van Rossum, the inventor of Python. Recommended, but due for a new edition.

Programming Python (Lutz; Oreilly & Associates): also slightly outdated, but highly recommended by people who have it. More of a reference than a tutorial.

Python Documentation: the starting point for all official Python documentation including the Library Reference.

The Python Tutorial: a gentle but effective introduction to Python.

The Python FAQ: many questions and answers about specific features and problems. Come here when you can't find your question answered in any other documentation.

Language Comparisons: also known as Python vs. Perl vs. Tcl vs. Java vs. the world. Most articles here are reasonably objective and balanced comparisons. Always pick the right tool for the job. Often, Python is the right tool.

Downloading Python for your platform. Both source code and binaries for a wide variety of platforms can be found there. However, if you are running a Linux distribution such as Debian or Red Hat it will be easier for you to obtain the appropriate package for your system from your distributor.

Regular Expression HOWTO: mastering those tricky but useful regexp's in Python.

Database SIG: a gathering place for people interested in and information pertaining to using tabular databases with Python.