Looking for sound effects for a space-themed arcade game? So was I, so I compiled a list of resources and sound effects.
SoundImage.org
Eric Matyas has a free collection of both music and sound effects.
Sci-Fi Weapons and Explosions SFX… http://soundimage.org/sfx-scifi/
Space Cannon
Laser Sound Effect
Quick Explosion
Hull Breach 3 (could also be the launching a photon torpedo)
Cyber Chime (Could be the approaching of a boss ship)
Power Rez 2 (could be good Game Over sound effect)
Power Rez 9 (another good Game Over effect)
Sci-fi Ambient Sounds http://soundimage.org/sfx-scifi-amb/
REZ DRONE 1 – A repeating sweeping electronic hum that might sound cool as ambience in a Sci-Fi game.
Spacecraft hum (could work well in background of game).
freesound.orG
Freesound.org has some decent sound effects, though you have to login to download them. Here were a few I liked…
Lasers
Good Basic Laser Sound: http://www.freesound.org/people/nsstudios/sounds/344276/
A Cool extended laser http://www.freesound.org/people/CosmicD/sounds/93021/
Good Mining Laser http://www.freesound.org/people/mazk1985/sounds/187405/
UFO Scanner http://www.freesound.org/people/peepholecircus/sounds/169991/
Big Enemy Laser Charge http://www.freesound.org/people/GeronimoGeronimo/sounds/338067/
echoing laser http://www.freesound.org/people/AndreOnate/sounds/135118/
Space Ships
Cargo Ship background: http://www.freesound.org/people/vumseplutten1709/sounds/320529/
Starship Bridge http://www.freesound.org/people/kaumodaki/sounds/245773/
Ship Passing By http://www.freesound.org/people/Sergenious/sounds/55849/
Mysterious UFO Landing http://www.freesound.org/people/sunfly/sounds/122679/
Spaceship white noise http://www.freesound.org/people/DrNI/sounds/34736/
Interesting Spacey noise (almost musical) http://www.freesound.org/people/GeronimoGeronimo/sounds/338065/
Tools To Make Your Own Sound FX
Make your own sound FX at http://bfxr.net
or https://www.leshylabs.com/apps/sfMaker/