Not much tutorials found in one place but you could find many in random places in web.
http://phonegap.com/[
^].
They're more than bunch of books on Phonegap,
Check here[
^]. Check their wiki page too.
Clickety[
^]
And watch their blog regularly for more updates.
http://phonegap.com/blog/[
^]
And I found some video tutorials in Lynda & Pluralsight websites.