It'll be my 1st time in Inzell next year too,Gary.I've managed to get a room in the village of Inzell only 500 mtrs walk from the track too.
If you fly into Munich,then it's a train to Traunstein followed by a bus ride from Traunstein to Bad Reichenhall(no.9526 bus).From Traunstein to Inzell it takes 30 mins.If you fly into Salzburg,then it's only 25 mins to Traunstein and the same as above to Inzell on the 9526 bus.All details can be found at http://www.bahn.com/i/view/GBR/en/index.shtml As Bavarian has pointed out,it's much easier from Salzburg to Inzell.
Speaking with Conkers a few weeks ago regarding accommodation and obviously Inzell fills up very quickly.There seems to be a few hotels in Ruhpolding(8km from Inzell).Expedia and Booking.com websites should sort you if you're struggling to find any suitable accomodation.Hope this helps Gary.