Coding to Say Just called Someone at [name of town] 23 minutes ago

Hi I need to put together some coding to suggest that we just called somone X minutes ago and have a message like 'Just called someone at [name of town] [XX] minutes ago' (or XX minutes and XX hours ago). The name of the town must be selected randomly from a list of say 300 names I will provide. The time between calls will be random, but want to be able to set how many calls it is to suggest we made per day.. ie if set to 10 it will randomly break up the day and work out when to show the messages.. New calls only to be started during normal business hours/days. So for example at 10pm it would say at least 5 hours ago - assuming a 5pm normal business hours. Also only business days - but variable). Finally, if we access site and it says 21 minutes ago etc and then refresh or access the site using another browser it must show the same results. Finally, as this will be on an [login to view URL] page need to probably be in php to a linked page so people cannot see source and know it is all made up! Thank you and those who show me something so that understand what I want would be much better. Thank you.