Where to get it?

Ok, so I've been working on integrating an arduino with a 3 axis accelerometer into a 3d environment, and it works just fine. Problem is there isn't a way to tell look left or right, as it's effectively a tilt sensor.

What I need to know, is where can I buy a digital compass... super cheap. Like maximum of $20 cheap.

XD I doubt that I can actually get one that cheap, but hey, it's worth asking. Maybe someone bought one and doesn't need it anymore and would be willing to part with it? ;D

Anyway, thanks in advanced.

Maybe this one?

Maybe this one?

That's a gyro, not a compass.

As far as I know, compass modules are pretty expensive.

This is the cheapest I've seen.

That's a gyro, not a compass.

Yeah, I know, but since the problem is with detection head rotation, gyro could be useful, as it measures angular velocity. Just a thought.