icy water will hurt the ham more than help him. They don't regulate their internal temperatures as well as larger mammals (cold hammish feet in the winter across the back of your neck when you're taking a nap is a prime example) Instead keep him in a cool, dry place out of the sun. A fan is all right but make sure its not directly on him and he's got somewhere sheltered from it because drafts can get hams sick. Frankly I live in Florida and that's what God invented air conditioners for but if you haven't got one I've heard some people on the board suggest getting a can of frozen juice or something of the like and putting it in a corner of the hamster's cage. The idea is that as it cools it will also help cool the cage and the ham can get as close or as far from the differ in temperature as it wants. Once the can (or whatever) is thawed, replace with a new one and freeze the first for a replace and repeat thing. Of course common sense says to put something under the can so that while it thaws the condensation doesn't soak through the hamster bedding and be aware you're little guy might lick, nibble, etc the can once its thawed. Remember, your little guy is walking around in a full fur coat and is built to sleep underground during the day when its hot outside so you have to take steps to watch out for him. Being aware of the problem is a good move and if you keep paying attention the way you are you'll do just fine with a new little ham. Make sure you handle it while its still at the pet store so you can get a feeling for its personality type and have fun.
life and a house full of hams