Is it possible to buy upgraded versions of games you already own on Steam?

I already own Deus Ex: Human Revolution - the regular edition, and it is linked to my Steam account. I would like to buy the 'Augmented Edition' which is now at a 75% discount (I like the soundtrack, and want the making of videos).

Right now it doesn't seem possible to buy the other version. Is there some workaround?

Solution 1:

It depends on the game.

If you have the regular edition of Civilization V, for instance, you are able to upgrade to the Game of the Year edition, which features all but two of the released DLC, plus the soundtrack.

If such an upgrade is available, the "buy" option will change to "upgrade" (as long as you're already logged in to your steam account).