1) the missing delivery is a very hard quest that is easyly broken. It actually covers three quests.
Check this thread for a complete solution
trevor/wagon/tingalf Look for a explantion by Kiya
2) Troll quest: kill trolls in cave and report to Homer (iirc) in the farmlands.
3) You can do it with the person of your choice and gain some expirience (iirc)
4) Go around the back of the house to the left. Pick the door and enter. Or ask Lenian (??) for the key . You have to be a member of the thiefsguild.
