Well, I'm new here but I do have some positive donation responses for you:
Ripley's Aquarium
1110 Celebrity Circle Myrtle Beach, SC 29577
Carowinds
P.O. Box 410289 Charlotte NC 28241
Walt Disney World
P.O. Box 10000 Lake Buena Vista, FL 32830-1000
Just send a donation letter 6-8 weeks in advance
Kings Dominion
P.O. Box 2000 Doswell, VA 23047-2000
Tweetsie Railroad
P.O. Box 388 Blowing Rock, NC 28605
Ben & Jerry's Ice Cream
c/o I.C. Donations 30 Community Dr So. Burlington, VT 05403
Any NASCAR driver, just look on their fan pages for an address for an autograph and most of them will send a stock 8x10 picture signed. Most of them you have to send a self addressed, self stamped 9x11 envelope and they will mail it back. This is best done at the beginning of the season. The more popular drivers, like Dale Jr. (yeah #8), Tony Stewart, Jeff Gordon (boo, hiss), it is a hit or miss thing as they get so many request. Most of the new and up and coming drivers, Kasey Kahne, Martin Truex, Jr., Kyle Bush and so on are pretty easy to get. Also try the Busch drivers and the Craftsman Truck drivers, they are really easy to get.
Most of our donations come from good old fashion foot work. I take my kids, ages 10, 8, and 5, to the stores, restuarants, movie theaters,etc. and they ask for the donations. Do you know how hard it is to turn down a child versus an adult?
They always like to see what they can get.