The "Storyteller" Achievement requires you to speak to Calendar Man on each Holiday circled on the calendar located right outside of his cell in the Solomon Wayne Courthouse in Park Row. To get to Calendar Man's cell, enter through the back door of the courthouse, then go down the stairs to the right from where you enter.
The holidays needed for 2014 are:
January 1/ New Years Day
February 14/ Valentine's Day
March 17/ St. Patrick's Day
April 1/ April Fools Day
May 11/ Mother's Day
June 15/ Father's Day
July 4/ Fourth of July
August 16/ St. Roch's Day
September 1/ Labor Day
October 31/ Halloween
November 27/ Thanksgiving
December 25/ Christmas
If waiting for the holidays isn't your style, you can get this achievement offline by manually setting your date to the dates required.
(NOTE: You will not get a timestamp if you get the achievement like this.)
My advice (If you haven't started yet) is use the offline method to get all but one of the dates, preferably the closest date to the day it happens to be when you start this, then wait for that date to roll around and BAM, timestamp.
If you lose track of the dates that you do have, worry not, any date you have talked to him will be crossed out on the calendar outside of his cell.