These are the places I know of on I-40 through Arkansas:
The Sawmill- Forrest City exit. Was once a Cracker Barrel but now houses a locally owned buffett serving breakfast, lunch and dinner. Greens and breads are of particular mention and the meats are all good. Very reasonable. Contains a gift shop with LOCAL treats and offerings.
Whattaburger-Russellville exit. As recommended by the Sterns and their review is in the restaraunt section, Feltner’s Whattaburger has excellent burgers, fries and shakes.
The Altus exit offers several fine offerings. The home of Arkansas winemaking, Altus contains several fine wineries, including Post Winery, Wiederskellar, Aux Chateaux and several others whose names escape me. Wiedarskellar features a German restaraunt, Post has a wonder shop and includes locally made treats like Hoop Cheese and cottage cheese. Altus, which was once a small coal company town, has been reinvented as a quaint small town of boutiques and restaraunts. Fat Tuesdays is an excellent Cajun Creole place, and they also own a great pizza place next to them. Kelt’s features pub fare such as sandwhiches etc and a large emporium of imported beers at reasonable prices.
Ozark Exit has one of the best "Q" places I’ve ever been in………The Rivertowne Inn, featuring pork, chicken and beef bbq, and several combination platters. The okra is to die for as is the slaw. Also in Ozark is a place of which I can’t remember the name, but is easily found at the end of the exit by a Phillips 66 gas station. Large juciy hamburgers and awesome handcut fries and onion rings.
Alma exit has a Braums and if you head up on 71 , traveling through some pretty Ozark country, approximately 6 or 7 miles out of Alma, on the right is the Catfish house. All you can eat fried catfish, crab, shrimp and oysters are featured along with awesome hushpupies. Sides are served family style and all is absolutely scrumption. A combination meal ran about 8.95 per person.