I have many battle stories on this topic, but my basic advice is - only use an image for as long as you can prove you have rights to do so.

There are leeches out there praying on image use, but there are also reputable sources.
Not my job to enforce whether someone has the rights or not, but if I'm going to use an image myself, I know I need to be sure I can prove a reputable source.

I've had to negotiate for website owners that thought it was OK to use any image they saw on the internet (until Getty came calling). Trust me, phone calls negotiating with Getty are no fun.

I've also experienced people getting images from a legitimate free source that was later bought out by another company that waited a couple years .. and then came after the client for using 'their' image for 2 years. They wanted payment for 2 years use at their desired rate. (yeah, no)

It can get ugly; try to be safe out there. <grin>

I do not work here, but the benefits are still awesome
Make your sound your own!