The current stable Psycopg release is 2.7.3.1:

There is currently no testing release.

See the install page for instructions about how to install Psycopg from source.

On PyPI

Since version 2.7 psycopg2 is available on PyPI as a self-contained wheels package. You can just use:

pip install -U pip # make sure to have an up-to-date pip
pip install psycopg2

without needing to meet the prerequisites required to build the package from source.

Older versions

All the Psycopg releases (both branches 2.0 and the now obsolete 1.0) are available for download.