Should be easy enough to figure out with a 12V test light. If you don't
already have one, go buy one ($5 ??) at AutoZone or equivalent. Connect the
ground clamp to a good ground and start probing where power should be
starting at the 40A and 10A fuses. Then go to the blower relay amd make sure
that there is always power at connections #30 and #5 (relay will be marked
with numbers at the connections. If not,  fuse #12 or #7 is bad, or bad
connection. Now, turn on the blower motor, and probe connection #87 at relay
to see if the main contacts are closing & passing current thru to the motor.
If voltage is present ,relay is OK, if no voltage at #87 then relay contacts
are not closing, and you need to ohm out the coil at #85 & #86.
    If the relay seems OK go on to the blower motor and see if 12V is
present at the (DB) dark blue wire (BAT side of motor) when the motor is
supposed to be running. If voltage present, and the motor isn't running,
then either the motor is bad or the motor isn't completing the connection to
ground thru the black/tan wire thru the blower switch to ground.

Here's a link to the
schematic:http://i5.photobucket.com/albums/y174/bashful24/Scan10144.jpg