Latest stable: Luminescence 1.3.
If you want the most up-to-date version, check out the Git section below.
First, you should read the README.
And here are some guides I wrote, if you want details:
~/.luminescence/config
(using the default plugins)My personal Git is probably the place where you'll find the latest version.
If you like social networks, you can find it on GitHub. I try to keep it updated too.