Free sound effects for game developers - The free sound packs that can be downloaded contain several hundred sounds, for a total of about 3 GB. All SFX are in high resolution WAV format and available for instant download. Everything is royalty-free, commercially-usable and no attribution is required.
Don’t forget to download the free 1GB sound pack available on the Bluezone Corporation homepage.
Browse the free sounds list : Free SFX for game developers