The brown creeper is an enigma, a small inconspicuous bird, solitary, difficult to find, see or hear. It is a bit mysterious.
They're easiest to see before the trees fully leaf out. Look for large trees on land that would be canopy-covered in truly green seasons. Parks will do, and county nature reserves. Wooded residential neighborhoods in Minneapolis or St. Paul would be good. (Our wooded backyard is good.)
Creepers are misnamed. A dictionary definition of creep is to "move slowly and carefully in order to avoid being heard or noticed." Creeper motion is what you notice.
They move quickly, nonstop, searching furrows, cracks and crevices of bark on large trees, mature trees, old trees with rough bark. The bird uses its tweezer bill to poke and probe for insects, pupae and eggs, and spiders and spider egg clusters.
It's a wonder they can find and grab food as they scoot along in short, rapid hops.
Creepers have a well-defined searching technique. They begin at the base of a tree, spiraling as they climb, hunting all the way. When they run out of trunk they return to the bottom and begin again, or fly to another tree.
They also will take suet from feeders.
The bird is cryptically colored, brown and tan with a light breast, all of it blending well with the bark on which the bird hunts. Movement is the clue, a blur of bird on bark.