Duathlon training plan

I agree with Brian -- the run training should be preparing you for what is essentially a half-marathon effort.

I think I romanticized this distance when I first looked at it. It's going to kick my butt.

I was toying with the idea of a sprint tri the weekend after followed by a 10k race two weeks after, but I think I'll leave out the sprint tri. With that schedule, my first tri won't be until June and only a sprint so I think I'll be putting off swimming until after March which should leave me with plenty more room for running and cycling. 

I'll probably be aiming just to finish as I haven't really done any races of this distance. Up to this point I've only done a sprint tri and road races up to 10 miles. I'm doing my first half-marathon on Feb 12 and then this race March 25. I won't be living in this area next year so I figured I couldn't pass up on doing this race while I live in the area. 

As for cycling, most of my rides will be inside for at least the next month due to not having enough sunlight. I'm guessing just following Jorge's trainer program plus a long outside ride once a week will give me a good cycling base?

Yes, Jorge's plan plus a longer outdoor ride on the weekends should be good. You might also want to try a bit of a race practice if you haven't done many duathlons before. E.g., run 3 steady, ride approx race distance, then run 4. This should help to give you an idea of how each leg in the race affects the next.