Just started driving, next thing its knocking, then its gone

[truckman72]

Six years ago during my 8th grade year I got my 69. After working on it for 5 years I get it driving May of my Senior year of high school, and then I leave for college. I get to driving it a couple of times of year when I am back home for college, and when its not snowing or raining. So when I was back in town during the week of the 4th of July I was out cruising around, the next thing I knew it was knocking and it continued to get worse and worse. At that moment I knew that it was gone. So, I drive the remaining minute home, parked it, and have yet to drive it since. Every time I go in and look at it, I remember all of the work that i put into it and it is just sitting, not moving. At this point I have decided that I am going to drop a new engine into it, but with me away at school I can't really do that. So I have made a deal with my Dad. I find it and he'll drop it in for me. So now I am starting my great search to upgrade from my old 327 carborated engine to a newer LS fuel injected engine. So my question is where do I start looking and what is the best way of locating a donor vehicle? Any suggestions or ideas would be great!