Workout Routines for Faster 200 Yd. Freestyle?

Hi Everyone, I have been swimming for 10 months now and after my 4th month I decided to compete in the 200 yd. freestyle. I had a time of 2:44 which included no racing dive and only 4 flipturns. Five months later and 20lbs lighter I have no idea of what type of training to do and how much. I am presently swimming anywhere from 1500 meters to 4,500 meters per day, six times per week with all flip turns. I also do about 10 sets of 25yd kick sprints per day on my back with my arms behind my head scattered throughout my swim. I have another meet coming December 9, 2007 and like to have my lung capacity much better by then and 40 seconds faster. AI swim in the 50 to 54 age group. Any help would be greatly appreciated! Thank You, Steven