My blower stopped working suddenly on my 04 Trailblazer. I figured it was the resistor but as Murphy's law would have it, the battery died a few days later. I replaced the battery and the blower worked initially (about an hour) then stopped again. The fuses are good to go.
More than likely it's the blower motor itself which is bad. This can be from a "dead" spot where the brushes meet the motor or what have you. Then some vibrations got it to a "good" spot and it decided to work again ... until it hit the bad spot again when it stopped. You can pull the blower motor and see if it will work by applying power directly to it. You can test my theory a little bit by manually moving the fan a little and applying power to it. Do this several times until you get the fan around 360°.