Chase Jarvis (an Aperture user himself) has an education site called Create Live where the classes are free for the live sessions (they sell the recorded versions). Scott Bourne is teaching a three week Aperture class on Create Live - the first session was this last Monday. There are two more live classes over the next two Mondays. You can sign up here: http://creativelive.com/courses/
and the viewing screen is just createlive.com/live. There's chat while the course is going and they have staff monitoring that; while it's a chance to ask questions, there were six hundred people on there for the first class, so the odds of getting the question picked up seem a bit thin. Scott's also provided an email to have questions sent in to be addressed during the third class - it's firstname.lastname@example.org
For me, one of the really helpful segments was going into full screen mode and then noting that you can bring up the adjustments, metadata, etc. with the H key, which I did know What I hadn't focused on is that you can then lock those (and put them anywhere on the screen) - the full screen with the long adjustment bar is a fantastic interface option. You can bring up a film strip too and lock that if you want or just have it pop up. The other cool thing in that segment was if you have say a floating adjustment HUD, and if it's over a true full screen image that you're working on (one of those things you just can't do in LR) you can get rid of it blocking your window and leave only the one adjustment slider that you're using visible by holding down the shift key, so there's just one floating slider on your image that's taking up your full monitor - really cool.