I've found a few sources of IMHO pretty good sharp pointy things: Blade Studio and Greylight Archives. I think there's also some stuff at Ironclad Studios, but I can't remember for sure.

There's also a German (I think) site with lots of weapon props I liked, but my mind's blanked on the name or URL.

A trawl through the other big archive sites such as RuntimeDNA or 3D Commune should also come up with something.