A quick search did bring up my 2005 Owners manual, but not the Service manual.
I think in the end, the owners manual may be sufficient for any regular maintenance.
Unfortunately for me, before I had the service manual, I was worried there was more than "maintenance" needed for my skis.
Luckily, by the time I changed the oil/filter, spark plugs, old gas with new gas, and added a pint of SeaFoam, my skis ran perfect this year, despite running poorly last season.
Avoid paying high service fees. Search (if you can, which I have yet to find free) for a service manual for the ski. Then you can work on it whenever, just like a dealer would. I hate paying for anything, but I could not find it free anywhere. Hopefully lovbytes will give a link or something so you dont gotta pay. Although i find it totally worth it if a free version is not available!
My skis ran like crap for nearly two seasons. So if yours are running with a rough idle, which may cut off on idle but run fine with any acceleration, consider swapping sparks, oil, oil filter, and air filter, and any old gas that may be present.