Here's what I usually do in situations like this one:
Hit eBay and try to find a seller who calls himself digital-ostrich. This guy is a former game programmer who specializes in selling vintage computer games. If you buy any game from him and can't get it working, he will help you to the best of his near-unlimited ability. If this fails, he will give you a full refund.
I bought Day of the Tentacle from him. He sent me two discs - one with a backup copy of the game which had been modified to run on modern computers, and one original DotT disc to use as a coaster. (It's not piracy if you include an original copy of the game!)
I absolutely suck at using a computer, but I have never experienced any trouble with a game I bought from digital-ostrich!
Oh yeah, if you don't find the game you're looking for in his eBay shop, you can always contact him and ask for it. Chances are, he can get it for you anyway.