How to export Apple Mail Email Addresses..

I am going about an email-gathering process in order to analyze addresses I want to use for future marketing.

One resource of qualified leads is my 5 year old Gmail account which has all my correspondence 'banked' -

so I want to extract and put into a list form (spreadsheet, csv) - all of the sent-to and received-from email

addresses that i have accumulated. Since Gmail doesn't natively export email addresses as a list, I must

go through the process of either a POP or IMAP download to an email client. I decided to set up Apple Mail

with an IMAP configuration for the purpose of offloading all of my gmail into Apple Mail. That is currently in

progress - I am running the "sync" feature at the moment - figure it'll be a half-day or so to process through

it.

Then comes the question, which i forgot to consider - and I am not sure about this because i normally use Thunderbird...

is there a way to export all of the Emails from the Apple Mail folders once they've downloaded from Gmail - into a format

that can be 'read' by an email extraction app - i.e., .csv, or tab delimited, etc... I see stuff about "Address Book" being

exported, but nothing specifically referring to the email addresses themselves.

Hope this question makes sense and thanks for any advice or second opinion on whether there's a better way to do

what i'm trying to do.

Thanks

Mike