Nuisance Trophy: Initiate every dialogue in the game (others have posted that this is obtained by picking every demon-Strong Bad, but I got this when I spoke to the last character after the party)NOT CORRECT
Hedge Trophy: Sculpt all 4 hedges. At the Track, by the useless wall, in front of the castle, and on the side of Marzipan's house.
Strong Sad: Get Strong Sad to pop into the frame everywhere possible. Chocolates down the hole to the KOT, pile of dirt in front of the Strong’s house, say two bad things to Bubs. ON SECOND RUN-THROUGH THESE ARE THE ONLY ONES NEEDED.
Take a look at the post http://www.telltalegames.com/forums/showthread.php?t=5887
for the specifics on each trophy!