Depends,

If you do a forum search for "Music", you'll find several posts listing places to get music, but if your music tastes are different then you may not like the suggections.

Istripper Discord has a dedicated thread for music suggestions by users.

Spotify has a user Braveheartr4 who has a public playlist "Songs to Dance, Strip, and Seduce", and of course many other songs/albums you may like as strip songs.

If you do use Spotify remember to mute the istripper spounds, or deselct the music in your Istripper profile to prevent you hearing 2 songs at once.

Ulltimatly, your idea of strip songs may diffey wildly from anyone elses ideas.

If you still want to look in the web, do a search for "Legal MP3 Downloads", there are several sites with stuff there,.

You could also convert any CD's you own to MP3 and use the songs from those, but thats obviously a legal gray area depending on where you live. Search "Format Shifting" for your country.