The Pro hand exercisers are pretty good. I remember buying my first one about 10 years ago. Mike Piazza use to do sets of a 100 in each hand about 2-3 times a day. There are better ones called hand crushers and I think Jason England uses them
Dumbell and Barbell wrist curls will strengthen you wrist and forarms. You could do them from a seated or standing position. You dont need a lot of weight, a nice weight high reps will do. Dumbell and Barbell reverse curls will work the upper part of you forearms.
Wrist Rolls is a very good excerise. You attach a weight to a piece of string with a wooden handle and just roll the weight up.
Swinging a weighted baseball bat will also do the trick.
Lastly for the fingers you could stand near a wall, place you fingers on it and start to do a standing push up off the wall. Lots of martial artist preforms this
Or you could take some corks stick them in-between you fingers and try closing you hand. Both finger excersies were use by Allan Kennedy for his center deal.