Google has a decent article on how to
regain access to your account here:
http://support.google.com/android/bin/
answer.py?
hl=en&topic=2500700&ctx=topic&answer=2569768
That will still not solve everything but start
there and then go through the bullets
below.
Some workarounds to try before reading
ahead:
1. try entering null as password. (together
with your google username)
2. try entering your username without
@gmail.com
3. Combine 1 and 2
4. Call yourself from another phone,
answer, without hanging up press the
home button, then menu button, settings,
try to disable pattern-lock
5. Call yourself from another phone,
answer, hang-up, directly after hanging up
start pressing your buttons like a madman
for My
Downloads. Other things though are lost
if you haven’t backed them up manually
with a 3-rd party application. Example
on things you will lose: Call logs, text
messages, application settings.
This is your 3 step solution
1. Factory reset your phone (links to
Android device manuals can be
found below, it differs between
devices)
2. Setup your phone just like you did
the first time you unpacked it (use
the same Google Account if you
want your old contacts back!)
3. Restore any manual back-ups and
install your previous applications
from the My Downloads list.