Ever since I have heard about lookout towers I have been in love with the idea of staying in one. I came close last year and booked one, the closest to Los Angeles, but alas I did not make it. The good news is that I have done a lot of homework and am gladly sharing it with you here.
There is plenty of information on the web about these fascinating accommodations, since I have yet to actually visit one I will just list the info and you can look into it on your own. Please let me know if you discover something I should know about staying at a lookout tower.
From Fire Lookout Wiki Page:
"The typical fire lookout tower consists of a small room, known as a cab located atop a large steel, or wooden tower, however sometimes natural rock may be used to create a lower platform. In some cases, the terrain makes it possible so there is no need for an additional tower and these are known as ground cabs. Ground cabs are called towers even if they don't have a tower to sit upon."
Here is a map I made of all the closest lookout towers up to the Northern edge of California.
View Lookout Towers and Cabins in a larger map
Here is a vast page of state by state lookout tower information including rental information.
Here is a listing from an interesting website on unique places to stay called Odd Inns and Uncommodations
Here are some direct links to lookout towers and cabins in California that you can rent within the states park and national forests websites:
Bear Basin Crescent City area
Girard Ridge Mount Shasta Area
Post Creek Shasta area
Oak Flat in Sequoia. This is closest Lookout Tower to Los Angeles as far as I know.
Just to wet your appetite, this is some time lapse film a friend of mine shot at the Girard Lookout Tower after I told hi you could rent these places and he could not believe it.