Lindsay:
It easy to make. First, go to downloads.com or another place like it, and get the program called bootCD, then the bootCD will talk you through the process of creating an OSX bootable disk. The program will ask you what utilities you want on the boot disk. In your case DW3 and any others you think will help you in an emergency. BootCD works fine, I've used it, but it is very very slow when booting the computer, so many people think it's frozen or crashed. It's not, just slow booting so patience is important. The boot disk loads normally by hold the "C" key. Once booted you can run DW3 and rebuild your directories. I suspect you'll have corruption, if so, DW3 will ask you if you want to fix it, so don't leave the computer, until then. Good luck!