A good site to find free photos with no copyright issues
Where can you get plenty of free photos from?
I have sometimes used sxc.hu. There are tons of free photos on sxc.hu, on all sorts of different subjects. Just be sure to read beneath each photo what the permissions are for using the photo - or even link to the profile of the person on that site who provided the photo, as sometimes the permissions seem to differ slightly.
The person who uploaded the photo is the one who says how it can be used. Some of the photos can be used without any linking back at all required, and the person does not even want notification of where you used it. However, some want at least feedback on where you used their photos, and, some want to be credited, or linked back to.
There are really very many there that say they don't need any notification at all, but it's nice and good manners to go back and at least tell them thanks for uploading that photo, because it came in handy for you, and you can tell them where it appears, so that they can see where work they are proud of, and put effort into, appears - it may also encourage them to upload more photos that appeal to you. sxc.hu is a super resource for free photos.
It has a good search facility top left of each page - just type in a keyword, and then hit "enter" on your keyboard, and pages of results will come up, showing many photos you can look through, and click on to view larger and read the permissions below or next to each one - remember to visit the photographer's profile if you are not sure.
Generally, the free photos are meant for use in projects, or for displaying on your own website or website profiles, and not for making copies of and reselling them - and that makes perfect sense - if somebody else took the photo and is offering it to the public to use, free of charge, it would not be right to make copies of it and sell them. It is also not encouraged to add a whole bunch of these photos to your own site, offering them as free photos. If you want to offer free photos to everybody looking for or needing them, take those photographs with your own camera yourself, before displaying them on your site. Do not offer the same free photos that somebody else already is - they took trouble to take the photos; you can too.
There are many sites offering free photos with no linking back required. Just google "free photos" or "free public domain photos". Good luck!