In reply to ElaineG:
Start easy - don't go for the full-caffeine coffee and a slab of cake on the first outing. Begin with a mild herbal tea, and work your way up. It might also be best not to leave the gear shop at all for the first two visits.
If you really want to make sure you don't overdo it in the caff, though, a spot of climbing can be a worthwhile distraction. You can usually tell when you've done enough, because your arms are tired. But never too tired to lift chocolate cake.
(Sorry, not been to the wall for about five years either, so some of the climbing related advice above may be out of date)
Just enjoy yourself, break in slowly and DON'T watch videos of people on Beastmakers. Getting regular partners will help enormously, as everybody has a different approach - so three or four people going at the same problem helps to widen your repertoire of moves. It also means that you don't immediately go off on an intensive regime and blow out those knees.
Fun, social climbing first. With cake. After that, you'll know exactly where you want to be going.
Martin