This is the second Elmore Leonard western I have read and was the original one I was looking for after reading about it in Vintage Hardboiled Reads (come back, August!). I'll quote the synopsis here and you should go over and read his review, because it's quite good, though I disagree with him somewhat about the ending.
Powerful Frank Tanner and his men have a suspected Army deserter and his Apache wife trapped in a shack. Seems this deserter killed a friend of Tanner's six months earlier, and he wants him dead. It's turning into a big spectacle as humble Bob Valdez, a part-time constable from the Mexican side of town, arrives at the scene. Valdez goes down to talk the man into giving himself up. Tanner's men start firing and Valdez is forced to kill the man to protect himself. The man turns out not to be the one Tanner was after. Later, Valdez wants to take up a collection for the widowed Apache wife, but gets plenty of hostility from Frank Tanner on that idea. On one trip to see Tanner about the money, Valdez is ridiculed, humiliated, and left to wander and die bound to a wooden crosspole. But Valdez survives, and when he comes back he comes back as a different Bob Valdez. A Valdez from the past...
Valdez is Coming has a similar intensity to The Hunter, but it suffers being read right after it. It's laden with a strong morality (the simple, honest man who does good against all odds) and though compelling, it burdens the read a bit. Though I think this morality stands out more when put up against the starkness of Richard Stark's world. I think it's also a question of taste. Because it really is a great read. It's smoldering the whole way through and you get caught up in it.
The main character and his slowly revealed backstory is excellent as well. In both of the novels that I read there is a strong underdog theme, where the natives and Mexicans are portrayed as good, strong and silent victims whose moral and practical superiority ends up winning the day. I see what Lantzvillager was talking about when he said that Leonard's westerns are "a re-imagining of the style". These books seem a little '70s PC. It's not a bad thing, since kickass mexicans with apache blood and training are pretty fucking cool, whether they really one out against the white man or not!
I did have some trouble with the ending.