Life is too short to have urges like that left sitting around when you can buy the things for $200 on ebay....
I'll have to go to Maine to shoot it, and who is going to teach me how to use it. I don't know anyone that has a crossbow.
I'm out of luck, for now.
Look at the pictures of crossbows on ebay. Most if not all of them have a foot stirrup; you put a foot in the stirrup and then pull the string with both hands on either side of the lock until the string locks to cock the thing, then load an arrow, take the safety off and shoot.
Many of them are in the 150 - 160 lb range and you may or may not be able to pull that to cock it. If not, you'd have to reduce the tension of the bow and all modern bows are set for poundage with allen-head screws; you simply back the screws out to reduce poundage, but both screws HAVE to be set the same number of turns out. You turn the one a half turn, then the other a half turn, and so on.
Next you'd have to sight the thing in properly and I'd recommend that you toss the pin sights which come with them; NCStar makes a decent little holograph/red-dot sight for crossbows which is $20 on ebay.
After all that you're ready to shoot but, like I say, the crossbow was never anybody's idea of an ultimate weapon; the English longbow and Turko-Mongol composite bow were the ultimate weapons between the fall of Rome and the advent of usable gunpowder weapons.
Simpler, cheaper, easier to use and more interesting to my thinking for those interested in weaponry of past ages would be a modern flintlock rifle like they use for deerhunting in PA.
The basic flintlock really was the ultimate weapon of war for two centuries from early 1600s to early 1800s. It was the first effective firearm which was cheap enough to produce to be useful.