Unfortunately there is no easy way to migrate from one Google account to another. The difficulty is compounded due to a Google account is not the same as a Google Apps Account even if they have the same username.
Here are some links that deal with this issue:
Google Web History Can’t be moved - http://googlesystem.blogspot.com/2007/04/google-web-history.html
How to transfer bookmarks from one Google account to another - http://googlesystem.blogspot.com/2007/04/google-web-history.html
Managing Profiles in FireFox - http://support.mozilla.com/en-US/kb/Managing+profiles
Joshua Lynn
Here is a link to another article on Lifehacker that deals with migrating email.
http://lifehacker.com/5521065/how-to-migrate-email-from-one-gmail-account-to-another
I used Outlook Express and IMAP to move from my server to Goole Apps hosted domain. A bit of a pain to go directory by directory but it did work.