Gitosis is a git repository management tool. It has features that make multi-repository, multi-user environments much simpler. The way you access the configuration is through git. You make configuration changes in your working copy, and then push them to the repo. These changes are then processed by git hooks to create/manage the repositories and keys.
One of the downsides of gitosis is that all administrators have equal permissions to add/remove keys, and there is no mechanism for users to manage their own keys. In response to this I have begun building Gitosis Web, a PHP frontend to gitosis that adds some extra capabilities and ease of use.
Many people are comfortable with Gitosis, and that's great. This tool doesn't replace Gitosis or say there are any issues with Gitosis, but simply that some workflows could benefit from an additional frontend.
Gitosis Web Readme
Gitosis Web is designed to is designed to be a layer on top of gitosis. Leveraging PHP and extra properties stored in the gitosis configuration to allow and administrator to control the entire file, and to allow individual users to manage their keys.
To install, you will need working installations of git, gitosis, php, and mysql. This system has been tested under linux, but might work on windows too (Assuming you have git in your PATH). Once you have this, make sure your apache user (probably www-data) has a checked out copy of gitosis-admin, and that it has a key setup with the gitosis server you want to administrate. You should add a "name = x" row for your adiministrator to the [gitosis] section, and an "x = pass" section to specify the cleartext password.
Once you have it setup, you load the web interface, specify the path of the gitosis-admin working copy, and provide a username and password. From there you can make changes to the gitosis configuration, or add keys to already specified users. Each user should get a group looking like [group user-stephen].
At some point in the future, I hope to add the ability to manage users without tweaking the gitosis.conf file, or allow users to manage their own keys. Allowing project owners might be a cool idea, but might make the interface too complex.