Right click,select properties and then highlight and copy the full URL. If it is a really long URL, you may not see all of it initially. Click in the address for the URL, use the right arrow to get to the very end and thengo backwards, selecting the entire address.
Be aware that since you will be linking to it, if it ever gets deleted or moved you will get the dreaded Red
X box wherever you are posting it to. Sometimes it is easier to copy and upload it but if it is someone else's intellectual property please make sure you ask for permission. Not only would that be taking their intellectual property but it also takes some of their bandwidth and some people get more cranky about that than the use of their photo/ Gifs etc...
Tim
