Apart from not using the gifs on the no-no list..easy way to tell if something is copyrite??
Open the picture and drag/drop it into Notepad............. see all that code??? Somewhere in there (if you know how to read it) is a copyright notice or at the least a registry to the computer of origin.
oe save it & open it in PSP & If you can't see any watermark or anything to show it's copyrighted...then you are ok..
but always leave a credit/thankyou if you use a piccy it saves all sorts of hassles!!
After all adding pictures are fun and not meant to scare folk from using graphics.xxx