The best thing you can do is to take a weekend Total Immersion class. Fantastic. If you can't do that, then get the DVD. If not that, then try out the book. Technique is everything in swimming and very few swimmers swim correctly. They are all powering with their arms and legs, swimming uphill and shortening their bodies. Water is 900 times denser than air so swimming is all about reducing resistance and not burning up all your oxygen trying to go fast.

Swimming more may get you there, but it won't ever be fun or effortless unless you focus on technique. I recommend TI because over the Y or other coaching only because I know that it is solid.