Yep, me too...
There is no load option for importing in the game, only export it appears.
I also tried to load it from a memory card (Xbox) and 2K5 does not recognize the old playbook, so sadly, the answer appears to be, no.
Time to spend a couple hours on a new playbook.
I remember all too well, it taking me several extra hours in making last year's playbook, due to the 270 plays, not being enough. Etc.
Don't get me wrong, it was fun to create (really makes you feel like you are coaching your team) but if I could start again with last year's, that would have been awesome.
Something for the wish list, I suppose. The only problem with that though, is, you can make formation - package specific roster changes that go into the playbook... which I assume may become a problem from one year's ESPN game to the next.