If you could post up the pictures it'd help. On Craigslist I've noticed that most Trek 1000's and similar bikes sell for about $350, so try to bargain the price down a little.
I bought a Trek 1000 seven years ago for about $500 and I have not regretted it. This T1000 is probably better than the one I had cause I know at somepoint Trek decided to upgrade the model with a carbon fork, which is nice.
Be sure to find out how many speeds it has. If it's 8-speed it won't be compatible with the current Sora line because the new Sora has 9 speeds. You can still get the old stuff for pretty cheap so I wouldn't worry about it too much so long as you don't wreck your shifters.
The Trek 1000 is a good buy for the money. Not so great for racing, but if you're not doing that it will serve you fine.
Pros:
Cheap
Fast
Great for intro road biking
Cons:
Heavy
Handling could be better
Not very responsive
The cons aren't too bad given that you are not racing. Also the weight really isn't a factor if you don't live in a mountainous area (literally) and if it comes with a triple or compact crank you'll be fine. The wheels and frame are very durable, and will in my opinion outlast the life of the components. Good luck!