Let's see...
I've done one duathon (supposed to be a tri, but bad weather cancelled the swim) and one triathlon this summer. They are SO fun!!!
You will have NO trouble getting ready for it in a year!! First of all, if you haven't been doing much swimming or biking, start working on it. I was NOT a swimmer when I started about 1 1/2 yrs ago. I joined the Y and started swimming laps and read a lot on technique. I also have 2 training buddies that are good swimmers so they gave me some form pointers. I did quite a few BRICKS (bike/ run transitions). I would bike 10 miles or so and then run a mile just to get my legs used to what it feels like (very weird, like Jello at first!).
I kept up my strength training (P90X & Cathe) while training also, until about a week before then I tapered off and just did some shorter swim/ bike/ runs.
Let me know if you have ANY questions! I did mine on a Hybrid bike, but recently switched to a road bike and can't believe the difference! Also, see if there is a local tri club, I joined one and you find out about a lot of races, get discounts at the local running/ bike stores, etc. And maybe find someone to train with! HTH!
Jess