Right click on Picture you're looking at, click properties.
Copy "location" and paste it into your post, OR, the preferred method is to save it to your computer, THEN upload it to either your own server or a free site (photobucket, etc). Then, paste it as a photo here.
The only problem with copy/pasting pics is wherever you're copying it from, leaves you completely open for Internet Espionage. Say you copy a pic called Big2.jpg. Well, the person hosting that pic sees that people are linking his pic to some internet site, so he uploads a nasty pic to his server, taking the place of the original file but with the same name, and a lot of times, the pic replacing it is not that pretty, and most times vulgar.
James