If like me you enjoy some old games and they aren't available on GoG.com, i suggest you try and search for them in this website http://www.oldgames.sk/en/
They have a bunch of old gems that come in an installer with dosbox pre-configured so all you have to do is install and play!
I have helped myself for a copy of star wars tie fighter (one of my favorite games of all time), a system shock 1 working like a charm and copies of elder scrolls arena and daggerfall (these are available for free in bethesda's website but the ones i got already have dosbox configured)
One important thing to mention is that games larger than a certain size require points than can be gained by purchase or by submitting stuff relating to a game that they don't have like a review, screenshots, manuals, etc...
Anyway, i hope this post helps someone out there