Add files to an ISO?

[Kevin83165]

Under Windows, I used to make an ISO image from a disk then use a program called Ultra ISO this would allow me to add files to an ISO, then I would simply burn it back to a blank.

Can someone give me a quick tutorial on a way to do this under OS X? (can this even be done with disk utility?)

 

[mad jew]

Does it have to be an ISO? If you use a DMG, it acts pretty much just like an ordinary folder in Finder.