Hi
Although it is long time ago HoMM released, I still prefer that. I have heard some roumors saying that a new kind of expansion was on it's way. Something about a exp-pack (Horn of the Abyss) or (woG (In the wake of Gods)).

Does anybody knows something that I dont?

Might and Magic III does not have any expansion at all.

Heroes of Might and Magic III does however have the 2 official expansions, some games with easy campaigns, lots of places where you can find new campaigns and new maps and In the Wake of Gods has been out for some years

The best place to find maps, campaigns and WoG is here: http://www.celestialheavens.com/

I'm currently on a student network and some idiot student has done something he shouldn't do on Celestial Heavens, so I'm afraid I can't find you the direct links to maps, campaigns and WoG being as the network I am writing from is banned by CH. But you should be able to find them by googling a bit.