Even though Canonical Launchpad team announced they would be holding back two components, they now changed their mind and Launchpad is open-source, starting today. You can view the announcements here:
The development wiki is dev.launchpad.net. Right now, only Canonical people can edit it. Everyone will have access to it eventually, but just for these first few days things will be controlled because there will be a lot of eyeballs on it, and Launchpad needs to figure out the right strategy to allow the good edits while preventing vandalism and spam. The wiki explains the basics of how to learn your way around the code, make patches, and get code review; these processes will evolve organically.