Just a less than obvious (to me) feature of sourcetree.
If you are cloning a remote git repository, you need to tab out of the Source path/ URL field to activate the clone button. The url will be validated at that oint. The url needs no special syntax working with gitolite, and even respects the host entries in your ssh conf file. So in my case a url of gitolite:workrepo is sufficient.
Sourcetree +1
