Sticky tensioner pulley...?
 

About 2 weeks ago I took the tensioner off to have it polished. When I took the pulley off it seemed to be really sticky - holding it by the bearing I'd give it a good hard spin and the pulley would only go 'round maybe 3 or 4 times before stopping and it sorta sounded like something was binding. When I got everything back together and started the car it makes one hell of a noise, kinda like plastic rubbing on plastic. I even took the pulley off and put it back on again thinking maybe I'd torqued it down too much (18 ft/lbs). Still the same noise. I haven't really noticed it before because I've never stood in front of the car while idling with the hood open.
The car's an '02 Hawk with around 20,000 miles on it, is this normal?

That pulley is known to have issues. I'd look at replacing it.

OK, thanks. I don't suppose there's an aftermarket tensioner pulley that's better/different than the stock one?

I just installed a Katech tensioner from Thunder Racing.

It's a manualy adjustable, nice piece. They have pictures on their site.

I thought that was just the tensioner - don't you re-use the stock pulley with the Katech tensioner? While we're on the topic, since the Katech is manually adjustable how do you know how tight to make the belt?

Yes, the stock pulley is installed on the Katech tensioner.
Your options are to buy a stock pulley or you could dress up the engine bay with an MBA billet pulley.