cx_Oracle is a Python extension module that allows access to Oracle databases and conforms to the Python database API specification. Below are the steps i used to setup cx_Oracle, with 11.2.0.2, python 2.6 on Ubuntu 10.04 (Lucid Lynx).
1) Installed Oracle 11.2.0.2 Enterprise Edition on Ubuntu (You can also configure this by just installing the 11.2.0.2 instant client too)
2) Download cx_Oracle Source code from http://cx-oracle.sourceforge.net/
3) Install python-dev on ubuntu (Or else you will get compile errors (Like file Python.h not found) when you try to install cx-oracle)
– sudo apt-get install python-dev
4) Login as root
5) export ORACLE_HOME=/u01/11gr2/db_1;export LD_LIBRARY_PATH=$ORACLE_HOME/lib:$LD_LIBRARY_PATH
6) cd <dir-where-cx-oracle-untarred>/cx_Oracle-5.0.4
7) python setup.py install
Once it is installed you can run the sample program from http://wiki.oracle.com/page/Python to make sure it works.