http://www.droid-life.com/2010/08/03/manual-android-2-2-update-for-motorola-droid/
This site has the download for 2.2 although I waited for the OTA. It also has the beta flash, but again I'll just wait for an official release. But when you read through the site they recommend you clear your home screens before you update. Whether it really should be done or not I don't know but I did it and my upgrade has gone flawlessly. If it helps with a cleaner install it's worth it. Plus you are going to want to reorganize your screens since you are getting 5 of them anyway.