www.hrs.de had some great deals, but I got mine on
www.spg.com
Cancelled the ArabellaSheraton Grand (160EUR/night during last weekend of Oktoberfest) for the Bogenhausen (120EUR/night). Booked these both 3 weeks before my stay (3-5Oct).
The Grand looks newer from the outside, but apparently the rooms are nicer in the Bogenhausen (search this thread for more details - someone has photos posted of both). The Bogenhausen has a 22nd floor pool that overlooks Munich and is beautiful.
Both hotels are across the street from each other, and 1 block away from the Arabellastrasse stop on the U4, 7 stops from Hauptbahnhof. The hotels are in a quiet district and close to the English Gardens. Safe, but far away from downtown.
Hope it helps.
O