Its a wonderful area you'll be staying at. Great Paddling... BUT especially in the spring, beware of rapidly rising river levels. I'm not a native but have been a regular at the Pnet Ozark Rendezvous for many years.
You're best info here will be from theBob.com, Wildernessweb, PaddlinPam, Mozark, pblanc... and some others. There are a bunch of us here who are have been paddling there all their lives and are better informed than I, especially once you get off the Current and Jacks fork rivers.
The Current River between Salem MO and Eminence is classic! Pulltite or Round Spring campgrounds are good places to base camp if that's your pleasure. Otherwise there are gravel bars that can be camped on all along the way, but again -beware- I've personally never seen rivers that can rise faster than those in the Ozarks in spring. Don't want to wake up swimming... 8ft overnight is what they often advise planning for on the Jacks Fork.
Otherwise, the Buffalo R. below Ponca is beautiful from what I've seen of it. Above Ponca is pretty serious whitewater, Ponca to Ozark Campground will keep you on you toes at 3-4 ft levels, below that things flatten out and get scenic. I've never gone below Hasty myself, so I'd refer you to others for that info. There are other fine rivers about also... the Black, Eleven Point, Mulberry if you like whitewater, St. Francis (+ Big Creek), North Fork (of the White R.). Lots of places to paddle and fish.
You might want to skip over to the "Getting Together and Going Paddling" board and ask there - there are several Ozark Paddling threads going right now with a bunch of Ozarkian natives active. They might see your questions quicker over there and be more helpful than I can be. By the way, a bunch of us will be paddling the North Fork this spring, based at the Twin Bridges campground. C'mon by if you're still around MO/Ar and are moved to join in.
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