Here is a part of a tutorial on making an ISO from a Cd and the command to do it.
Make an iso image of a CD:
dd if=/dev/hdc of=/home/sam/mycd.iso bs=2048 conv=notrunc
CD sectors are 2048 bytes, so this copies sector for sector. The result will be a hard disk image file of the CD. You can use "chmod a+rwx mycd.iso" to make the image writable. You can mount the image with "mkdir /mnt/mycd", this line in fstab: "/home/sam/mycd.iso /mnt/mycd iso9660 rw,user,noauto 0 0", save fstab, "mount -o loop /mnt/mycd". Then the file system will be viewable as files and directories in the directory /mnt/mycd. You can edit the image as you wish, and the new file will be "/home/sam/mycd.iso" dd does not write to CD's. You need to use a burning utility, or the cdrdao command.
The full artical is at http://www.linuxquestions.org/linux/...ything_With_DD