[philbo]

This actually happened to me a few years back and, eventually, they were very helpful.

The key for me was providing sufficient proof that the account really was mine and really had been hacked. I gave them as much information as I could remember/check:

* some contact names

* some tag names

* some recent thread subjects/recipients

* name of the person who first invited me to GMail back in the day

* details of any labs settings, theme etc

* mailing list subscriptions

I wish I could remember the email address I used to get in touch with them but, as I said, this was years ago now. I definitely found it somewhere publicly available, albeit buried somewhat.

HTH