I use Apple Mail and have:
A) nearly 80,000 e-mails
B) 10 different POP and iMAP e-mail accounts
B) over 30 rules
Any tips or resources for getting all my e-mails, accounts and rules transferred into Gmail?
For the pop3 email accounts (if you've left the mail on the server), have you tried going to Settings > Accounts > Check mail from other accounts (using POP3): Add a POP3 mail account you own?
When I migrated my mail a couple of years ago I set up gmail in the apple mail client using iMAP, and manually dragged things into gmail. A combination of that and adding the POP3 accounts took care of my needs, but I wasn't moving 80,000 emails :)
The post linked below looks like it would work, but it'd require some local server administration, not sure if you're up for that.
Obviously, if you went this route you'd have to find an alternative to the mail server since that's windows only
I have no research to back it up, but the rules you may have to be a manual process