How do I re install my Canon A530 Power Shot without the disk?

You can go to the Canon website and download your driver disk from there. Just go to the following website:

http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=DownloadDetailTabAct&fcategoryid=320&modelid=12914

You just have to choose the version of your Operating System and then download what you need.

Depending on what version of Windows you have, and what type of software you are running, you may not need the Canon disk. If you have any type of image editing software from the last couple of years, as soon as you plug your camera's cable into the computer, you should get a window that pops up right away and asks you what you want to do with your images. You can then move them over, edit them, email them, or whatever else your software will do.
If you are running at least Windows XP SP2, or one of the last couple of versions of the Mac operating system, again you should get a window that pops open as soon as you connect the camera to the computer. The operating system will again give you the choice of what you want to do with your images.
If you do have one of the previous mentioned versions of operating systems, but nothing is happening when you plug in your camera, you may either have an issue with your camera, or with the cord.that you are using. Try another USB port on your computer.