My search engine is Google.
First, search for what are you looking for.
Second, click Images
Third, click tools
After you click the tools this will appear below
***Click Colour and choose " Transparent" ***
Also, if you want them in high resolution, click Size and choose " Large "
This is what I get:
This helps me so much and I hope it will help you too! 
images on google the majority of the time aren’t royalty free so you wouldn’t be able to use them as overlays (:
there is also usage rights option right? Click on creative common license
yep there is but this thread by the looks of it didn’t use that so they’ll be copyrighted
Yepp!! But still it’s safe to ask backgrounds from the forums and give credits to them in the end of the chapter.
Yeah if it’s been shared on the forums it’s most likely royalty free
yes!
