Check some easy, obvious things first:
1. As the guys said, drop the pan and change the filter and fluid.
Drain the converter also.
Look for little pieces of friction plate in the pan or in the filter, they will look kinda like big East Texas ticks - Ha. If you see any of these little brown pieces, time for some serious work.
2. Check the Bowden cable that attaches to the throttle linkage. Pop the ball socket off the cable end and check the adjustment. It should be adjusted so that the cable pulls out easily, then hits a harder resistance as the slack is all out. At this point it should just pop on the ball with no slack or no resistance.
Turn ther white nut to lengthen/shorten it accordingly.
3. Check the vacuum line to the modulator. It runs from the back of the intake manifold down the left side of the tranny.

DG