We have a nice collection of Zombie Sound
Effects available in the Horror Sound Effects on freesoundeffects.com.
Plus a category of general zombie sounds if you’re looking to make a
movie about zombies.
The above sounds are available for professional licensing to be used in
commercial projects.
But we also have a section of the same types of monster and zombie sounds available in the Scary and Horror Sound Effects for free download
to be used in educational and personal projects (these do not include a
license for commercial use).
We also have some awesome Royalty Free Horror Music and Royalty Free Suspense Music available for licensing in commercial projects and youtube videos available at our new Royalty Free Music site at royaltyfreemusicclips.com

You can also get music for youtube at royalty free music clips stite. This music is guaranteed not to trigger any copyright flags on youtube or your money back.