Not really sure. Most places I've lived we haven't had a ton of options on pricing so haven't dug around.

The approach to utility regulations varies a good bit by state, and things are always changing so I doubt there’s a good lookup beyond the data the federal government collects.

https://www.eia.gov/electricity/state/

Although, the states that are “energy deregulated” will often have a marketplace type website where you can compare suppliers. In those states, the utility commission sets rates for your local utility to run the transmission and local distribution wires, but allows you to choose which supplier generates the power on the grid on your behalf.

Really, the best way to figure out utility rates in the US is to check with that state’s utility commission or directly with the utility that provides physical infrastructure in a particular area.