The stamps on this set are from Lizzie Anne Designs' summer release - aren't they darling? The Cowboy is actually an older single, but the Cowgirl is from the new Giddyup Girl set.
Both images are colored with SU markers. Their hats are stamped on separate cs, cut out, and adhered for a bit of dimension. The chipboard ampersand is from Cosmo Cricket's Storytime line, as is the dp.