Looks like Old Town doesn't sell sit-on-top kayaks anymore. But REI had quite a few of them. Once you find a make and model you like, you can see where you can get the best price. It's also good if you can try out different models first (yes, some places let you get them wet!). Maine Sport in Rockport has a pond and so does Belgrade Canoe and Kayak and he'll dicker on the price. Wilderness Systems had some nice looking ones.
"There is nothing- absolutely nothing- half so much worth doing as simply messing about in boats". Wind In the Willows