What power conditioner will help in my situation?

A very inexpensive alternative is the Machina Dynamica Flying Saucer (a catchy yet uninformative title for this wonderfully efficacious audio accessory) inserted into the unused AC socket right next to the socket into which you insert audio or video component power cord.
Check if an unused AC outlet is built right into the base of the fan itself.
Also, insert the same product into any other unused AC power outlets throughout the listening room with its one shared power line circuit.
One of my listening rooms also shares a line with fluorescent lights, household appliances, ceiling fan.

The best configuration in my system -- after years of experimenting -- is isolation transformer > power conditioner > power regenerator. Nothing else comes even close in terms of sound quality.

Power condition will clean it up but you'll have to choose wisely as most lag the current, which in turn makes the amp work harder and runs hotter.

I ran a dedicated circuit, bought a power conditioner for my audio/video components, and bought an 8' power cord for my amp. End result is power conditioner cleaned up all noise on the audio/video components and the amp running directly off the designated circuit has no noise.

I didn't post what brand conditioner I bought for a reason...it was Chinese built! *lmbo

I wanted to add to my previous post. It would cost effective to replace the ceiling fan with a decent newer model first. You may not have to add anything else to your entertainment system.

Thanks for all your responses. I think I will go the dedicated line route.
To clarify, its not a constant hum, only when I change the fan speed I can hear a low frequency thump in the speaker. I know- don't change the fan speed- Thought maybe a regenerator would work but will look into a dedicated line. Thanks again.