Touring - What gear ratios would be good?

So me and a few friends are planning a trip this summer across the country. The bike i've chosen to use is a Lemond Poprad. I know that this is probably not the ideal bike but it's steel and i like the way it fits. I also plan on using it as a commuter for around town before and after the trip. After talking around and looking on forums I've found that this will work. If people could do it back in the 70's i figure it can't matter too much, and I will be using a trailer. What I'm wondering is what I can do and what people think would be the best way to get a better ratio of gearing on the bike.
Right now I have a double in the front, 46 and 38, and a 9 speed, 12-26 in the back. I'm thinking I could either get a triple in the front or get a bigger range in the back, or both. I don't know if my deraileur in the front will accept a triple or if my shifters will take a triple and what it would entail to make it work. Basically I am just wondering what people think would be the best way to do it. I plan on talking to some bike shop people but thought i would get peoples opinions on here too.
I've been using this bike on road rides on the hills and have found the gearing to be ok, I just tend to have to push the big hills whether I'm feeling it or not. I figure with the weight I will be pulling it would be nice to have some lower gearing.

You could put a bar end shifter on the left side to shift a triple der. and stay with your current shifters for braking/rear der. For a crankset I would get something with MTB gearing like a 22-32-44 or around there.

If you put a 34T cassette on the rear you'll need a long cage der. too.

All of these can be found pretty cheap.

I am not familiar with that bike, but on a couple bikes that I have added a triple to I was able to use the same shifters and front derailleur.

I used a 46-36-26 with a 11-32 for the TransAmerica this Summer and found it adequate, but wished for just a bit lower 3 or 4 times in the Appalachians (it was fine in the Rockies and Cascades). I since swapped the 26 for a 24.

Having a high gear for flying along down a gradual incline, or on a flat with a nice tailwind. But on tour I'd trade it in a heartbeat for the lowest low I could find. I had a pretty low setup when I climbed the North Cascades Highway in Washington last summer, including a 24-tooth granny. But on the steep sections I kept searching for a lower gear, which just wasn't there! I would have loved to have a 22-tooth granny, and a larger gear on my cassette!

A wide range is great, but if you have to compromise, make it on the high end, and preserve the lowest gearing you can! Just my opinion.

First thing I'd do is pick up the trailer, and take the unmodified Poprad out for a short tour. You may like the trailer, but it's best to make sure before you start modding your bike.

If a trailer really doesn't work out for you, it's critical to make sure that you'll have enough heel clearance for panniers. (It might not, since the Poprad is made for cross racing rather than general use.) If it doesn't have clearance, I wouldn't use it.

If the trailer does work, I'd go for a triple, as low as you can get -- 24 or 26 for the granny. 48/36/26 will be fine, esp. if you can get a 12-28 cassette. You might be able to get away with the double FD, but the part isn't that expensive and a real triple FD will ensure it can actually cover the range properly. AFAIK you won't need to change shift levers.