I am a newbie learning Python/Django...
Am using the following tutorial located here.
Created a mysite database in MySQL 5 running on Snow Leopard.
Edite
The problem is that you are missing the Python module that interfaces with MySQL.
See the Django docs for get your database running which further points to MySQL notes.
However, if you are just going through the tutorial it is much easier to use SQLite backend which is built-in to Python. No drivers, server, etc. needed.