Unfortunately the only choice right now is artaylor's cable.
If you want to make one, the information is on the wiki (see my sig for links), general consensus is that if you cannot build it with the info in those links and the knowledge that a Samsung e810 cellphone data cable(SERIAL, NOT USB) has all the pins needed, you should buy one.
PS, I found a $0.38 chip to replace the "filtering" schematic, it is a tiny 6-leg surface mount chip and will fit under just about any connector shell. The common name is USB Host Terminator, or Upstream port terminator, I started the $20 USB thread on purpose with that information.
Fact is that the TV cable should have that 38-cent part in it and a USB cable on it, and they can make buckets of money selling them at $20.
I sold my GP2X and am unable right now to walk people through building their own cable. If serious they should take an electrical circuits course and pick up some basic skills, or there might be a textbook or beginners handbook that could teach you the needed skills.
I thought the original poster wanted to do a hackaday mod, was I mistaken?