There are tons of creeks all around, I'm an arkansas native and i enjoy the hell out of our area. Some summers are pretty dry, but since we had an awesome spring and winter, we will have a pretty decent early summer that may carry us through until fall.
There are several class 3-4 creeks, and quite a few notable 4-5 runs. If there isnt any water in the area, there is a dam release area in malvern, about 2 hours away. I live about 30 minutes from ponca, the start of the buffalo.. and about an hour and a half from buffalo city, the end of the monster. We usually car pool down to "rockport" and spend the day playing in some great surf.
Just look at americanwhitewater for some info on locations.. and check out topozone.com for info and put-ins. But seriously, arkansas is beautiful, and very friendly.
there are several paddlers that wouldnt mind showing you the area, just drop me a line