And if not, then where could I find it, save for used physical copies on eBay and such?
Yes, when you buy the EE here on GOG you'll receive the classic version as well.
That is awsome to hear. Just one more question: How does installing the classic version actually work? Do you get a separate entry in your owned games list for both games or do they have some sort of shared entry and installer where you have to choose which one you want to install or something like that?