It is one of the most amazing journeys you can take. At each turn on the cliff road you think the view can't get any better, but then it does! You, shouldn't do it all in one go, but the Stop-over towns are very disappointing.
Carmel: Boring and twee.
Monterez: a bit tacksville
There are a few little woodland log cabin places on the way (near Carmel, if I remember correctly. They're in the Rough Guide). They were full when we tried to stay there so book in advance.
Also, if you're going North from LA to San Fransisco, a little drive further North to Stinson Beach is a good bet. You drive through a completely fab redwood type windy windy road, and Stinson Beach itself is particularily comely. Enjoy