Depends on the state and their counties. In Tennessee I can vote early from 8-4:30 M-F. In Davidson county (Nashville) they have more open hours and have early voting at all major libraries.
We have voting in all the libraries plus a few other places. But they open at 11:30 and the lines are going down the sidewalk. It's not as bad as it looks, though. I got through in a couple of hours.