legally you can't, they only offer updaters on the website as I am sure you have found.
They might sell you a set of disks, or you might be able to buy them on ebay but you'll not know what you are actually getting at that point, or you might find a friendly canon owner who'll send you a copy through drop box etc. afterall these programs are of no use to you unless you have a canon, and as you have a canon you should have the programs.
If you only download the pictures from camera, you need to change the setting of the camera communicates with the computer. It's reall easy:
1) On the camera, push the "MENU" button
2) Toggle over to the second set of tools (the last one on the right)
3) Toggle down to "communication" and change it from "normal" to "PTP"