Photos and images are everywhere on the Internet. Of course you are tempted to pick up any of the thousands of Google or Flickr images. But are you sure all these ones are for free?

We could say that 99% they are not. In fact, if you don't have explicit authorization to use a photo, or you don't know who owns it, almost for sure you will use it illegally.

As a matter of fact, you don't want someone to steal your writing, so it's better for you to inform about photos copyrights before using them. Photography is a profession exactly as writing, and owns to be paid.

There are also some places in which you can get lots of free photos, but the other side of the coin is that these images are, usually, of very poor quality.

There's a solution to all this. It's called iStock. It's a collection of professional photos that you can see in preview and then buy with a cost that is depending on the resolution. In this way you can download a preview photo for free - of course they are marked with their logo - and try it on your cover. When you're convinced, you can buy it.

Apart from that, it's quite cheap. We talk of prices from 2 to 15 dollars, or more if you want the highest resolutions. Moreover, the website has a good quality control - mostly are photos from Getty Images - and a vast archive.

They have a "term of use" contract, by which they allow you to use any images on you cover up to selling 499,999 copies.

There are some other websites of good quality. One of these is Shutterstock, that is quite similar to iStock.

The main difference is about buying: on Shutterstock to download images you have to buy a subscription of one month as minimum, in which you can download at maximum 25 photos each day. The good deal is that they are also in vector format, so if you can use Illustrator or another program to edit images, you can adjust them and modify them as you wish.

Dreamstime works in between iStock and Shutterstock: you can make a monthly plan or you can buy with credits. Still, it has a section with free photos.

We'll give you another option. In this website, called Freeimages, as the name says there are free photos you can use, with suggestions of paying images on iStock. Even if you can find something interesting, it's not really good quality and the number of photos you can find are quite limited.

The third option is excellent if you want something very special: we're talking about the official site of Getty Images or Corbis. Quality is magnificent, prices are higher.