Navigating a Bike Purchase (for Touring/Commuting)
I recently returned to the US after a 6 month stint in the UK. In the UK I spent some of my weekends doing 100 mile rides on my Raleigh Town & Comfort to see more of the country. I enjoyed riding so much that I have immediately felt the itch to get riding again now that I'm back in the States, and have planned myself some routes ranging from overnight trips to a couple weeks. All that remains is to get a bike.
I see basically see three options: 1) get a new touring bike (probably an entry-level one like a Fuji or Surly LHT), 2) try finding a used touring bike, or 3) convert a used mountain bike or hybrid into a touring bike. It is worth noting that I would like to do some off-road riding but obviously don't expect to be able to handle anything too rough (on my Raleigh I was fine on gravel and chalk but had a hard time on sections that required properly knobby tires – steep ascents on chalk or just about any surface after going through some mud, that sort of thing). Also, my permanent home is in New York City, and I'd like to be able to use the bike to commute as well, which unfortunately means that theft is not totally unlikely.
The way I see the situation is as follows:
1) Obviously this is the easiest option, but also the most expensive. I'm a graduate student on a stipend that lets me be comfortable, but doesn't provide much wiggle-room for making a $1000 purchase lightly. I'm rather concerned about the possibility of theft if I go this route. I'd be tempted to keep this at my parents' house and get a second, cheapo bike for commuting, but I'd also feel like I'd then be somewhat cheating myself out of reaping the full value of the bike I'd invested so much in.
2) Used touring bikes don't come up very often on Craigslist. They're easier to find on eBay, but you don't get to check them out before buying, which makes me a bit nervous. I've seen old Cannondales and a Schwinn Voyageur SP for $200-400, but I feel like every time I look at threads on this site people are talking about vintage road bikes (that seem comparable to me) being only worth $50 tops. Is it likely that I'll end up sinking another $400 into replacing the headset or crankset or something and not saving myself money anyway?
3) I've read about successful conversions of mountain bikes into touring bikes, so long as the chainstays aren't too short. I like this option because new-ish mountain bikes are readily available for cheap, and I imagine that (so long that the bike has the braze-ons I'd need) that my "conversion" could be as simple as changing the tires and putting on bar ends to give myself an extra hand position. My Raleigh was comfortable enough for me on my two-day trips, but I never took it out longer than that to know if I could spend a week or more on it. (For what it's worth I'm a 23-year old guy with a high level of physical fitness who doesn't mind much.)
The extent of my experience with bike mechanics is removing the wheels and handlebars, adjusting the brakes and derailers, etc. Nothing serious. I don't know anything about gear. However, I don't mind doing research and I quite enjoy getting into geeky technical details. The problem is that I'm not sure where to look for the info I might need (or what that info necessarily even is). I've been looking at Sheldon Brown's site and mytenspeeds mostly, but I sometimes feel like a lot of it is going over my head. Again, I find it a bit disconcerting that every time I investigate a bike model on a forum like this, it seems like there's a $100+ discrepancy between what forum members deem a fair price and what it's advertised for, and I'm not sure I know enough to avoid getting swindled.
So I guess what I'm looking for is A) advice on what the "best" approach might be and B) what resources are out there that I can consume to become more comfortable in my knowledge of bicycle mechanics and quality.
Sorry for the long-winded post that is rehashing issues that I've seen plenty of other members bring to the forum.