There are a couple Japanese places in Pueblo that serve some good sushi; I haven't visited all of them, but one of my favorites is Miyake's. It's just off Hwy 50 West, tucked into the little strip mall near Starbucks, Adolfo's, and the liquor store. It's a small restaurant, so if it's a weekend you might want to call ahead. But their sushi is some of the freshest you can get in landlocked Pueblo, and they also have wonderful udon dishes.
Suehiro's also has good reviews. I haven't personally been here, but I've heard good things. Sushi Garden is another great place if you're looking for a wide variety of sushi, but in my opinion it's not QUITE as good as Miyaki's. Close, but not quite.
