> Being relatively new to Vanagon ownership I'd appreciate
knowing what
> items of regular and/or preventive maintenance should be done
and at
> what intervals.

from the old days, when vw gave you a little Warranty &
Maintenance booklet with your bus ...

Every 7,500 miles / 12,000 km <about every six months>
- engine oil/filter change
(me personally, i'd do this every 2,500 miles / 4000 km. oil is
still cheaper than engines. ;)
- check brakes for proper functioning; check thickness of front
brake pads

Every 15,000 miles / 24,000 km < about every twelve months>
- all the stuff from the 7,500 miles service
- check for exhaust leaks/damage
- check fuel system for leaks
- check crankcase ventilation system
- check EGR system (except California models)
- check ignition system (ignition wires, distributor cap, rotor
should be replaced)
- replace spark plugs
- replace ignition breaker (points. this was before electronic
ignition)
- replace fuel filter
- check tension of v-belts; adjust as necessary
- check engine idle speed; adjust as necessary
- on diesel engines, check and adjust valve clearance.
- check cooling system; replenish coolant as necessary.
- check oil level in transmission; check final drive oil level in
automatic transmission
- check brake fluid
- lubricate sliding door mounting points
- adjust valve clearance and replace valve cover gaskets
- check dust seals on ball joints and tie rod ends.
- check boots on steering and drive shafts (cv joint boots).
- check and adjust headlights as necessary

Every 30,000 miles / 48,000 km (every two years)
- all the stuff from 15,000 mile service
- replace air filter
- check compression of cylinders.
- replace spark plugs (on California models)
- replace oxygen sensor and reset mileage counter (the OXS light
thingie).
  < vw later found out that the oxygen sensors lasted a lot
longer than two years. so this was dropped>
- replace automatic transmission fluid; clean pan, strainer and
replace gasket.
- replace brake fluid. replace every 2 years regardless of
mileage.

that ought to be enough to keep you busy. :)

good luck!
joel