Rich, I'm not a sage, I don't even like most spices hehe
I counted 3 questions in this post. Lemee try to answer them. Don't go by what I say, you should get more answers from others too.
Lube - Not really but needle lube helps some
Parts Diagram - goto the dixieairbrush site they have one. You should only have to take apart the 3 tip/nozzle pieces for maintenance. here's the link:
http://www.dixieart.com/Vega_2000_Schematic_from_Dixie_Art_Supplies.html
Cleaning - Depends on the type of paint you use. I clean with lacquer thinner , a nylon bristle brush (to swirl around in the cup), and paper towels. Keep a waste can (like a coffee can) nearby. I only take my airbrush apart every 10 sessions or so to clean it. Normally when I'm completely done for a session I just flush with lacquer thinner and take the needle out and clean that. Doing a complete breakdown and ultra cleaning is a little over-rated IMO. As soon as you spray the next color you have to do it again.
Most important don't worry too much. It's just a tool that sprays air. When the paint gets in the way it sprays that too.