how do i get mt hero back imprisoned?
Attack the village that's holding your hero captive and hope it doesn't die while being freed (because some amount of the freed troops will die), or send the player that's holding him captive an in-game message requesting the freeing of your hero. And don't forget to be friendly! n_n
Or you can just press button in rally point to kill him and revive him.
1) Speak to the player in game, you can usually agree a deal, either paying a small ransom within the rules, or setting a personal nap.
2) Send one of your cheapest troops on raid repeatedly until the traps are full, then hit them full on.
3) As above kill him off and revive, if that will be cheaper than the troops you would lose to rescue him.