prefs directory for current user

Hi,

Inside the Http protocol handler code, I wanted to find out the 
preference directory for the current user. E.g. if the user is 
"Default", I can call some API which will return 
"C:\WINNT\Profiles\Administrator\Application 
Data\Mozilla\Profiles\test\ds3ogj4e.slt". I need that API.

Why I need this:
I am making some changes in the protocol Handler and I need to store the 
current user's preferences in his/her directory. At startup, I need to 
read these files and act accrodingly.

In case this is not the right newsgroup for this question, where should 
I post it ?

Thanks and Regards
-Pawan