At the risk of sounding like a fanboy. I went ahead and registered my collection on Vgdex.com it really helped me with registering all my atari games. Not so much with my 5200 collection since I remember all I have but it allows me to know what duplicates I have and organizing my 2600 collection. That has saved me without buying repeats. Up to 57 of orginal 69 games. You can see my collection and record yours at that site vgdex.
