sachiker: This thread, "Sleeping in your car at Whitney Portal", has a good discussion of the walk-in camp sites. Just beware that the "Backpacker campground" is closed due to a rockslide and damage from last summer. So you need to use the "Ravine Campground". (I'm not positive that you cannot use any of the backpacker sites, so check that first.)

Regarding what people wrote above: "Hike high, sleep low" applies to higher elevations than Mt Whitney and the Sierra. I like Bob Pickering's advice: " Sleep at highest altitude at which you don’t get sick." Adding to that, it is always my experience that the first night sleeping anywhere but home or a motel room, you won't sleep well--just expect that. I will sometimes take two benadryl tablets when I go to bed, and they help me sleep more.

The second part about where you sleep is how much time you have before your hike. I come in from Fresno at 300' elevation, so always drive to 10k Horseshoe Meadows, and bed down for the night. (I'll take both Diamox and Benadryl for that first night.) That gives me Bob P's "sleep as high as possible" the first night. If you're doing Mt Whitney in a day, then the second night you want to be near the trailhead, so Whitney Portal is best for that. Now, IF you are trying to only sleep one night, then I suppose a Lone Pine motel is ok--I don't give much credit to just hanging at Whitney Portal for less than a day as giving you much acclimatization.

Here's the picture from the "Sleeping in your car" thread:
[Linked Image]