Upload images from your computer
The browse button on the add images page opens a box which allows you the search for images on your computer.

Finding images on your computer will vary depending on what type of operating system you have. Windows usually labels the main hard drive C and the CD player as D. So you might find an image directory in a place such as
/C/my documents/my images/

On a Mac things are somewhat different. Hard drives and CDs get whatever name has been given them by the manufacturer or owner of the computer.

If the folder containing your images is in an out of the way place on your computer, you might want to move the image folder to an easy to find place on your computer and then upload them from there.