None of my business but why would you want "thousands" of old emails on your brand new computer? Business purposes? If so, then you might want to talk to an apple professional about help in getting your mac to meet your professional needs.
Sorry, just kibitzing here but your problem raised my interest.
Peter or Bob might know. He also might know of a different email program that may be more appropriate to your needs if this is a business issue. They may need more information from you though.
cheers and good luck
grim
I decided to start using Apple Mail on my 3 week old iMac (20-inch, stock), and I can't seem to get all of my 1000's of emails from Gmail into Apple Mail. Apple Mail stored ~250 emails, and I need to be able to check past emails. Is there any way to have all my emails stored on the computer, so that I don't have to go on the Internet to look for them on GMail?

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