If you're looking for alert sounds, there are a few different options to consider. One option is to search online for websites that offer a wide selection of alert sounds. You may also try searching through a sound library such as Freesound, SoundBible, or FreeSoundEffects. Another option would be to use a royalty-free music library such as Envato Elements to find alert sounds. Finally, if you prefer to create your own alert sound, you can use a digital audio workstation such as GarageBand or Audacity to create your own.