You have agreed to do some chores for Captain Álarr in exchange for access to the murder location. Place notices around Lake-town for the guards.
'I need someone to go around town posting notices. That someone is now you! Take the stack from over there and put them up anywhere that looks appropriate.'
The stack of notices is in the guards' barracks in Lake-town.
You should take the stack of notices.
Notices can be posted in places all around Lake-town.
You should post notices around Lake-town.
Captain Álarr can be found in the guards' barracks in Lake-town.
You should talk to Álarr.