Is there a place to find the model histories of various AVR makers?

 I don't need the latest & greatest, but I do need some current output at 4 ohms.  I'd  be content with a slightly older model AVR, but I don't know where to find the model histories for the various manufacturers.  Is there a site that conveniently gives the (now discontinued) receiver models from the different manufacturers with links to the specs of each?
 
Thanks - Boomzilla