Panhandle Cowboy, by John R. Erickson. Lincoln, Neb.: University of Nebraska Press. 213 pp. $4.95.

With so many ''urban cowboys'' struttin' around these days, ''Panhandle Cowboy'' is just the kind of square-jawed, straight-shootin' account of a real-life ranch hand in the 1970s to kill a few misconceptions while creating new legends. It's not a spellbinder, yet the characters are living now and Erickson spins some of his yarns with such warmth that the selling of his favorite bronc could make the toughest redneck cry in his saddle.

Erickson manages to pack the book with informative nuggets and yarns about ranching and Western life today. The modern conveniences make it easier to survive, but the cows are just as ornery, and the life of the modern cowboy takes almost as much ''true grit'' as John Wayne made you think it did.