Here's a list from the AHA.
http://www.beertown.org/homebrewing/listings.asp
I don't know Maine all that well so here is a complete list:
Maine Ale & Lager Tasters (MALT) ID #: 000165867
PO Box 15
E Winthrop, ME 04343 USA
207 395-4554
brucestevens@maine-homebrew.org
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The Grateful Brewers ID #: 000165528
Farmington, ME 04938 USA
(207)778-9686
freetibet14@msn.com
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Southern Maine Homebrewers ID #: 000156158
410 High Street
North Berwick, ME 03906 USA
207-767-9939
erics@gwi.net
www.bru-cru.com/
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Portland Homebrew Club ID #: 000166077
50 Tyng St #3
Portland, ME 04102 USA
bodesbrew@yahoo.com
www.myspace.com/portlandhombrew