what is the difference between a 1969 fastback and a 1969 mach 1. Also where can i find out more information on 69 mach 1s  

Fastback is just a body style, just like a coupe.  Mach 1 is package that was available only on fastbacks, so all Mach 1s are fastbacks.  There is endless amounts of information on 69 Mach 1s all over the internet.  You just have to do a little research more specific to what you're wnating to know.  

Not to forget that there were also GT's made in 69.  Rare, but they are out there.  

I sure wish I owned a '69 Mach 1.  The 1969 and 1970 Mach 1's marked the beginning of the downfall of the Muscle cars.  At lease for Mustangs.  The Mach 1's came back in 2003, so I snagged one.