Blower motors typically stop because the brushes wear down and the connector wire gets tight and prevents them from contacting the armature. Once you get the motor out it is a simple job to take it apart. Just pry out the connector adapter and remove one screw on the end of the housing. Pull the motor out of the housing and examine the brushes. If they've run out of wire slack and you're reasonably handy with a soldering iron you can loosen the wire and slip it a bit in the solder connector. Oil the bushings and clean the impeller and you should be good for a couple more years.