I have a '97 Wrangler SE and for some reason the blower motor works only on high as of this morning. I checked all the fuses and it doesn't appear to be any of them. Any ideas?

In past Jeeps, there is a resistor pack that controls the 3 speeds for the blower motor. Most likely two of the resistors are blown as you only have one speed.

I haven't checked for a TJ, but I imagine it's a dealer only part.

HTH