Ok, I figured it out. I extracted the zipped files to the wrong folder. I extracted it to c:\hlserver\TF2 instead of c:\hlserver\TF2\tf.
The instructions for installation on
this page are a little confusing. They tell you to extract the mod to your game folder, which would imply TF2.
The instructions for installing Sourcemod are much better because they have a section for finding your root folder. Maybe that section should be copied and pasted into the metamod installation guide.