Tracking a simple phone call timer with cost

[Gilbert]

I am trying to create a small macro which would show me the running cost of a telephone call while using Skype. Since the base rate/minute varies depending on the country/location, I would like to be able to easily change/select this cost before launching the timer. Is there a simple way to do this? I have search in vain the Internet for an existing program to do this, but all I found were timers to track your online costs which are way too complicated and CPU hungry for my simple application.
Any help would be musc appreciated.
Gilbert