Radio broken in my BMW+want to play iphone songs?

I can't see the radio stations in my bmw because the lcd display lights are broken. I want to fix this. I also want to be able to play my iphone songs. There's currently no way to input my iphone in the car. Is there something I can buy that would allow me to do this? I don't know much about tech, is a car stereo what I need?

Dependant on which model and age BMW you have might dictate your next step.
Cheapest option is find a second hand model the same from ebay or your local breakers yard.
dependant on the age of the car, this might have the facility for you to plug in an aux kit to the back of the unit (BMW sell kits to do this as it has been an option on many models for years).
Alternatively, you can pick up a new head unit from your auto parts store fairly cheaply these days, and many come with USB/aux in.

3rd option, keep your stereo and buy an fm transmitter for your iPhone, you will then have to scan through the radio channels on the car stereo whilst you have music playing to find where the channel is located (as you don't have the display to tell you)
Hope this helps