Hey BB,
Sounds to me like you have a good fitness foundation for cycling if you are doing 30 miles on multiple days. Very cool!
Don't fear the hills...just start finding some hilly routes and start practicing hill climbing. I don't know what kind of bike you have but it probably has gearing that will be appropriate for any of the hills on the Trek course. There are specific techniques for climbing hills that you can read about but for me it comes down to the following:
1) Relax. When you see a hill coming up, smile. Even if it looks like a monster steep thing just smile and if you can, laugh outloud. Sounds weird, I know. But it does work.
2) Release the death grip on your handlebars. All of that tension robs your body of strength. Think of flowing over the hill. Breathe deeply. Keep your head and chin up as you climb...don't hunch over as this makes it more difficult for your lungs to deliver oxygen to your muscles.
3) Find a cycling cadence/rhythm where you can work both in and out of the saddle. If you aren't used to riding/climbing out of the saddle practice it before the Trek.
4) When feel like you are at your limit on a climb, pick a point up ahead and focus on making it to that point. Or, tell yourself that you will do another 20 peddle strokes. Once you complete the goal, set another one.
When you make it to the top of the climb, let out a loud WHOOPIE! and don't care who hears it 
If you aren't from a part of Maine that has hills, try to find a place that does to practice. I'm up here on Mount Desert Island and we have lots of hills to choose from and it is a great place to bike!
Hope to see you at the Trek!
-traveller
"It never gets easier, you just go faster." -- Greg LeMond