check this tutorial:
Fundamentals of the JavaMail API[
^]
All about JavaMail[
^]
pretty good, it's all in there.
A web email account like gmail will not work for development, as they let you demand access on a limited base and will ban you when you fail with your login.
If you need a email server try HMail Server:
http://www.hmailserver.com/[
^] (auto-ban option to be switched off in settings!)