Help! No reverse?

I have a 98 blazer and one day I went out to leave and there was no reverse. I know my luck it's probably the trans, but hoping it's not. Also when you shift to nuetrel its drive, but drive gear still works. To use nuetrel you have to start it, put it in nuetrel and then shut it off. Some one said it could be the linkage or shifter cable.

Definitely sounds like it could be a linkage/cable problem.  I don't have the time right now to look up the procedure for adjusting the cable.  Hopefully someone else will.  Good luck.

 Shift cable adjustment
Adjustment Procedure

Ensure that the shift cable is not restricted.
Place the steering column shift lever into the NEUTRAL position
Position the shift cable to assume a natural routing. The shift cable must be free to move 20.0 mm (0.80 in) axially during the adjustment under adjustment spring loads.
Pull the cable end completely forward and release it. (When the cable is pulled completely forward and released, the adjustment spring will position the cable to its most rearward position.)
Notice: Do not pull the shift lever ball stud forward of the transmission shift lever ball stud during installation. Pulling the shift cable end forward of the transmission shift lever ball stud before installing the shift cable end to the transmission shift lever ball stud will result in a poor adjustment.
Connect the end of the shift cable to the transmission shift lever stud ball.
Press the locking tab IN in order to secure the shift cable to the transmission bracket.
If the vehicle is equipped with a transfer case, install the bolt and washer securing clip and the shift cable to the transfer case
Install the grommet to the hole in the floor panel.
Install the three shift cable clips to the body