The first thing you want to do is to head over to Google.com, or simply open a new tab if you're a Google Chrome user. Next up you're going to type in a search term for whatever image you want.

ex. If I search "apples and oranges" the following results will come up:

Now the problem with these results is there's no way of telling if any of them have copyright protection on them. Unless of course there were an obvious watermark over the image. But in this case there aren't any, so what you will have to do is to narrow down the search by going into the advanced search settings.

To get there you need to head all the way over to the right of "Search Tools" and click on the gear icon, then click on advanced search, like so: