This thread had the 60 gallon white ones. http://www.bostonreefers.org/forums/showthread.php?t=93636
Matt theres a place near CRA called seekonk supply, they seel all sorts of stuff like barrels and water holding containers, Jeremy told me about it before, i never actually made it there though.
Those Brute trash barrels seem to be the cheaper way to go though.
I just use a 44gal Brute from Home Depot
You may want to check out if your town has a conservation program setup. Mine does and gives a rebate with the 'Great American Rain Barrel'.
http://www.ci.reading.ma.us/Pages/ReadingMA_Water/Conservation/program
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Rain Barrels Rain barrels, when connected to gutter downspouts, collect roof runoff for use in gardens and other outdoor watering needs. Residents purchasing and installing a Great American Rain Barrel are eligible to receive a rebate of $25.
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http://www.greatamericanrainbarrel.com/