The best type of boots in my opinion are the boots that have felt soles. You can save money by buying the cheaper rubbery type soled boots but they are complete rubbish, you just get no grip and could end up have a riverside bath.
View more items on eBayThose rubber soled wading boots are really for duck shooting or other hunting which means you have to go across fields or muddy beaches. The best thing to do if you don't want to spend the money on felt soled boots is to comprimise and make your own. If you have an old pair of boots with rubber soles then you can buy a felt kite that will stick to the bottom of the boot. You can also get studded sandals that will slip over your boot and strap on, that makes more sence than slipping around on rubber.