So the fan doesn't work on any speeds at all?
Could be the fan motor has worn the brushes down over the years, Try give it a tap and see if the brushes free up and it starts to motor again.. motor should be above the passenger side foot well..
There will be a fuse for it too, Sometimes the shafts inside the blower motor build up dust/rust up and start to cease up which in turn increases current draw and pops the fuse..