So, how do you patterns like the Zel banner?

It's called "computer graphics". You make that kind of stuff starting with Photoshop, then get a 3d proggie and use that with photoshop. They aren't patterns. They're just shapes, barely ever filters (unless it's a n00b), text, etc.

Oh and taco is a ripper, so don't start liking his work. I on the other hand, don't rip.