When you find a picture, right click on choose "Save Image as..." (That is in Firefox, which you should be using instead of IE, but is probably similar in IE).
Navigate to the directory you want to save it in. You can save it with the name shown or change it.
Later, in HubPages, when editing the picture capsule to add it, click the using your own from your computer choice, then click browse and find where you stored it, and click.
After a couple of time, a piece of cake.