Hey. Does anyone know a website that has free to use sound effects you can use in a game / app? Thanks!
I really like http://www.soundsnap.com. You get 5 free sounds/month, and have to pay for more. They have really high quality sounds, and I can almost always find exactly what I'm looking for.
I prefer: http://www.freesound.org/ They're all CC licensed, and so long as you have a read through the licenses, you should be okay.
I'll second SoundSnap. All the sounds in Slope Rider are from there. Although a lot of users complain about the voice sound effects being annoying (I found most of the voices in SSX on PS2 annoying too so *shrugs*) but they are still high quality sound downloads. Just be prepared to scour the listings - there's loads of sounds! Oh and being able to turn off the voice sfx is coming in V1.1 of Slope Rider!
SoundSnap is definitely a good source. There's a lot of hit or miss, but they have enough variety across most categories that you should still be able to find some decent, usable material. I've been grabbing some great environmental sounds from there for use in a musical project. Freesounds.org is also not bad, but a lot of the sounds are poor quality. But then, they're free -- cost and royalty.