USB port stopped working

on my macbook pro (the left hand side one)

Do they wear out or something? I know it's the port because i tested multiple memory sticks and they work in the other port.

Anyone know what I can do.

There should be a hardware test application on your install DVD - try that first
http://www.thexlab.com/faqs/aht.html

Then you could try resetting the SMU
http://docs.info.apple.com/article.html?artnum=303319

If you are squeemish about all this take it to an Apple store