There is no 'easy' way there is but one way.
Go to something like
www.fototime.com and download the pictures to a user storage library. You then click on the picture in your library and then copy and paste the URL (the bit that starts with
www.) to pprune using the boxed 'landscape' icon in the toolbar. When you have downloaded the picture and want to post it here bear in mind you will need to click on it twice...so that the only thing on the screen is the picture...and then highlight and copy the url.