I've used my e-brake for more than just parking, and its kinda wore out. Is it adjustable, or do I just have to replace the e-brake shoes?

The rear drums are self adjusting anytime you stop in reverse. But if you've been abusing them, it might be time for some maintenance.

BTW, the rear brakes are more than just your "e brake", they also help you stop normally...

00+ have disc brakes. they should be completely self adjusting... your probably experiencing stretch in the cable, or you have other brake failure. there should be an adjustment somewhere inder the car where the cable splits accross to the two wheels

The adjustment is under the car on the drivers side.
You need to check your rear pads for wear first.

I would do close examination of rear pads for minimum thickness as called out by SilverBullet. Establish whether or not you need new pads, then based on that adjust the parking brake cable if necessary.

I've heard that the e-brake is actually a drum brake inside the disc brakes, because hydraulic brakes (the disc'*) can't be locked up long term, they tend to fade with time. (i.e. if the parking brake is set for days....)

when i replaced my rear disc, i saw nothing of that nature