I’ve found this page called “Unsplash” where you can get free images to use in whatever you want. They are truly free, you don’t need an account to use them, you’re not required to give credit (although it would be nice if you do it). I has no watermarks either, and no restrictions whatsoever.
I think it is very cool that something like this exist, and I thought you people might like it.
Also, if you happen to be a photographer and you want to upload some free pics, this is a good place to do it.