where to store app data

Hi Experts,
I have a data file that I used to store in the program files directory branch of my application.  But of course now in Windows 7, I can't write to this file because of permissions.  There must be a place where these settings can be saved to a file with minimal worry about rights?  What is the correct way/place to do this?   (location for app data and what API call to find the location?)

Thanks!
Mike