Do you remember those lessons on arguments passed through a variable? Keep your function, but have an argument that states WHERE the ajax leads to.
function simpleFunc( place ){
AJAX blah blah, leading to "place"
}
Call: simpleFunc("process.php");
And easier way to do ajax however, is to learn jQuery.
Code to start an AJAX commute:
$.ajax
Learn jQuery at http://www.jquery.com/
Good Luck!
If you need further assistance/advice, feel free to contact me.