I 've bought some from Creative Cutters and Flour Pot. 
I have gotten tons of cutters from foosecookiecutters.com; thelittlefoxfactory.com (you have to mail in your form with check but they are quick); pinenose, pinnochioproductions (just got my order yesterday) and am getting ready to order form thecookiecutterfactory.com. I've also ordered from other sites, but these have been my largest order.
I order mostly tin. Have some copper. I have close to 600 cutters and only one has rusted/tarnished. It's about 12 years old. All others are just fine. I dry as soon as I wash. I don't think spending 10 extra bucks for copper is worth the expense. This is only my opinion. My copper cutters were purchased as total bargains - $1 each and some I made using a kit I bought at Foosecookiecutters.
Good luck and have fun.
I love the copper ones because they are pretty enough to display, but they aren't sharp at all, which is their disadvantage to the tin ones.
I shop at a few places:
www.krittersinthemailbox.com
www.beryls.com
www.coppergifts.com
www.goldaskitchen.com (my 2nd favourite!)
www.thecookiecuttershop.com
www.downtowndough.com
www.frankencutters.com/fc
www.thelittlefoxfactory.com
www.cookiecutter.com (#1 by far)
www.pinenose.com
I have found that www.cookiesinseattle.com are really nice to work with and have quite a few hard to find cookie cutters.
here is a quick tip for drying your cookie cutters, put your oven on low, spread wet cutters on a cookie sheet and dry in the oven for a few minutes. No fuss, no muss, and no rust. =)
...here is a quick tip for drying your cookie cutters, put your oven on low, spread wet cutters on a cookie sheet and dry in the oven for a few minutes. No fuss, no muss, and no rust. =)
Oh man, I never even thought of doing that! What a great idea and I will definitely be using it from now on! Thanks a bunch! 
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