Question of the Day

I've been blogging for awhile on my own, but I've never been brave enough to add a picture. Now that I know how it's done, I'm still hesitant. How do we know what images are acceptable to use and which are protected by copyright? It always seems like the images up for grabs are generic shots of landscapes and barns, but what if you wanted to write a little blog entry about how much you love Al Pacino (just as a totally random example, of course)? Surely there's a picture on the web that could be used for illustrative purposes. How can we be sure that no one will come after us for using an image?