The stable versions of PyTables can be downloaded from the file download area on SourceForge.net.
Windows binaries can be obtained from many different distributions, like Python(x,y), ActiveState, or Enthought. In addition, Christoph Gohlke normally does an excellent job by providing binaries for many interesting software on his website.
You may be interested to easy_install the latest released stable version:
$ easy_install tables
Or, you may prefer to install the stable version in Git repository instead using pip. For example, for the stable 2.3 series, you can do:
$ pip install --install-option='--prefix=<PREFIX>' \
-e git+https://github.com/PyTables/PyTables.git@v.2.3#egg=tables
The latest, coolest, and possibly buggiest ;-) sources can be obtained from the new github repository: