I imagine that most of the better hotels in and around the west side will be serving a traditional Thanksgiving dinner. I would check with Fig http://figsantamonica.com/ in Santa Monica and the Montage in Beverly Hills or the Four Seasons http://www.fourseasons.com/losangeles/dining/ would be a likely suspect. Also places like La Cachette Bistro http://lacachettebistro.com/ in Santa Monica normally do Thanksgiving turkey and stuffing.
The Conservatory Grill at Montage Beverly Hills
225 North Canon Drive, Beverly Hills, CA 90210