Steam has an incredible sale going on through July 4th. The price of dozens of games has been reduced, and great deals are available for company-specific packages. The list of specials is too long to reprint here, but here is how much you will pay for the recent Might and Magic games:

King's Bounty: The Legend ($3.24): A steal at that price.
King's Bounty: Gold Edition ($9.99): That edition combines the basic game and the Armored Princess expansion.
Heroes of Might and Magic V ($6.69): I doubt the price will go below that point anytime soon.
Heroes of Might And Magic V Pack ($20.07): The basic game with the two expansions, but you save only $1 so if this is the first time you play Heroes V, try a standalone game first (either Heroes V or Tribes of the East).
Dark Messiah Might and Magic ($6.69): That's really how much that game is worth. Much cheaper than the Xbox 360 version.
The Heroes Pack ($26.77): That's Heroes V, its expansions and Dark Messiah. Again you're saving pennies compared to the indivial purchases. But there's a lot of gameplay in that package.
Disciples II Gold ($6.79): An oldie but a goodie, it will keep you busy until Disciples III comes out.

You really need to check out the other deals on the Steam site, I guarantee you'll find something to keep you busy this Summer.