The Radisson Hotel at the corner of Century and Sepulveda (right at the LAX entrance) is okay for spotting aircraft arriving on the north runways if you get a room on the north side. The glass sucks though and you can't open it. I took a few shots through it and they're not good enough for posting on airliners.net, that's for sure. I used Priceline and got this mighty nice hotel for $35 a night for four nights last October. They charge $10 a day for you to park your car though but you have in and out privileges.
When you bid on Priceline you pick the star level of the hotel - you don't find out the hotel unless one of them accepts your bid. Check out www.biddingfortravel.com to find out how much other people are paying for successful bids in a certain area. Otherwise you may overbid and pay too much.
Photographing aircraft since the Earth was flat and on Airliners.net since #338