Most cars made in the last 15 years do have the media buttons you mention. It shouldn't be difficult to find what you want.

You should also look for them on a separate arm in my opinion.

I've driven Peugeot that has this and it's a great advantage over my Nissan which has them on the steering wheel. Try finding the button you want when the wheel's anything other than straight ahead - Unfortunately Peugeots are French.........................

To turn off James Blunt?

Seriously, I often find I'm feeling for them when I'm stationary at an approach to a junction and in a queue and the wheels aren't straight ahead.

you can buy stereo head units which come with remote control units like you would use in the home.

then you can velcro the remote control unit somewhere easy to use when driving.

somewhere like an arm rest on the door usually makes a good location.