To increase your power, you are going to need to be stronger, but not just stronger. Your punch will need to have more speed and explosiveness to it. There is not just on kind of training you can do to be successful in this sport or lifestyle. If you just want more power and a big bench press, go into power lifting, but in this sport, it is not about how much you bench or squat, but how well you can incoorperate your speed, size, power, and explosiveness into one package. It's great to excel at one of these, but without the others involved your screwed.
After that ramble, contact ironman in the training forum and he is good about hooking up people with great training programs fitting there goals.