I was in the same boat as you when I got into tri's a 2 years ago. The best thing to do is join a masters program in your area. Having someone watch your stroke and give you tips is priceless, especially since its so easy to cheat. If there isn't a masters swim program in your area you should check out total immersion (www.totalimmersion.net). They have videos and the technique seems to work really well. And last be not least if you don't feel like buying videos and can't join a masters program then just do the time in the pool. Just like cycling takes time on the bike swimming will take time in the pool. The hardest part of doing triathlons is the swim and the more comfortable you can be in the water the better. Find a breathing pattern that works for you (I use 5 stroke/2 stroke) and get used to swimming longer distances (try to swim a little longer than what your first event will be) without taking breaks. Be ready for the unexpected, because chances are somebody will get in your way or kick you on accident, so just be comfortable in the water. I hope all this helped.

Joe