Good question, I'm not sure myself. I did a few .wav searches using both audio & all types searches & came up with a lot of spam. Traditionally I'd have searched using artist or title - .wav

Keep in mind one minute of wav format is about 10 MB (10,000 KB), so a 4 minute song would be around 40 MB (40,000 KB)

I'm not sure there is a high number of genuine wav files being shared, at least with a wide variety of choices.