I'd also like to know the IDE cable people use. Trying to find a 20 pin single row is proving a little difficult for me. On my test board I soldered connections, but I dont want to go through that again.
I have been using the standard IDE cable from a computer, and only using the top or bottom row of 20 pins. It works fine, and is readily available.
I don't know of any supplier of only 20 pin wide ribbon cable.