Motor type?
 

Looking to replace MAFS, vacuum hoses, etc. Before I buy parts needed how can I figure out type of motor? AKB, AUX, OR 40 valve. I have 2001 A8L 4.2 Quattro. Found a great link to replace 40 valve vacuum lines but if I don't have 40 valve not sure how useful will be for me. Thanks.

2001 A8L should have a 40 valve AUX engine.
Plastic covers over cylinder valve covers should have "5V" printed on them indicating 5 valves per cylinder.
Engine number will be found under the centre engine plastic 'pretty' cover. Look to right hand front of engine (your left when facing it) and find the vacuum actuator for the manifold flaps (theres two, look to the right hand one (your left facing it)).
You will find the engine number on the top of the cylinder block under that actuator (if its a 40 valve engine).
First three letters are the code - I expect you to find 'AUX'...

If the engine number isn't there, look to the left hand lower side of the block (right hand facing it) above the power steering pump. I'm confident yours is 40 valve though.