Car Noises

I have a 1995 Buick LeSabre and I noticed today that everytime I turn the steering wheel to the left it makes a thump thump thump sound. Could that possibly be my ball joint? If not what could it be?

It is more likely to be a bad CV joint, but it would be a good idea to also have the wheel bearing on the right front wheel checked.

For good measure, have the ball joints looked at, along with tie rod ends.
On a 15 year old car, almost any component can fail at this point, due to wear.