Github users: please read the "wiki" link at the top of the page before submitting issues or pull requests.
If you're really impatient, and you're familiar with Unix and ssh, follow the quick install instructions.
But if you want to do anything meaningful with gitolite you have to spend some time cuddling up to the docs. The complete online documentation starts here -- this is the best starting point for general questions about git, such as what it is, why you would need it, features, contact/mailing list info, and so on.
For convenience, here is a link to the master table of contents, which is very useful to search using your browser's search function.