calf raises! also weighted back squats and jump on the rower to get some anaerobic fitness. Row as hard as it takes for you to not be able to speak while doing it 3/4 times a week for 40 min and you'll be sorted.
Steve House's book (New Alpinism) has a big chunk on climbing specific work: specific exercises and also advice on general approach. He doesn't lean too heavily on machines – most of the routines that he describes you could do from the (dis)comfort of your own home.
