I adore roadside attractions. I have two key sources for finding them:

https://www.atlasobscura.com has a very high bar for inclusion. I fire it up anywhere I visit and see if there's something obscure and interesting to check out.

https://www.roadsideamerica.com has a very low bar - like a rock that someone painted pink and added googly eyes to and now it looks a bit like a pig. Any time I'm on a road trip I keep an eye on this (I use their inexpensive iPhone app) to see if there's anything worth a quick diversion.

I love both of these platforms. The Wikipedia "map" tab on the iOS app is also a great source of neat local oddities.