Unity Asset Store - Unity's asset marketplace for game makers.
Incompetech - Royalty Free and Creative Commons Music Archive
Kenney Assets - We've created over 40,000 images, audio files and 3D models for you to use in your projects. Thanks to our public domain license you're even allowed to use them in commercial projects!
ecrett music - Royalty free music composer, powered by AI
GameDev Market - GameDev Market is a marketplace for high quality, affordable 2D, 3D, GUI & Audio game assets, handcrafted by talented creators around the world.
Premiumbeat - Premiumbeat.com provides high quality Royalty Free Music.