Replace in Files (looping possible?)

[SpartanHokie]

I have a bunch of files that I want to do a search and replace on, but I don't explicitly know what files they are. They are defined by a specific extension. Is it possible to do a replace in files based on a folder and a given extension? Or at a minimum, could I do a replace in a VBScript method? I could go and get the file names from there and call a replace in file step for each filename I find. Thanks in advance!