Dell uses proprietary components and doesn't like to sell their products anywhere but on their website, so when Dell no longer offers it on their website it's a problem. The only route would be through Ebay or another online marketplace. Just search for "dell dj usb"...prices are in the $2-$5 range.
Hope this helps,
P.S. You may also want to invest in a rolled-up newspaper.
My dog chewed up my parents Dell DJ connecter to the computer, we have no warranty and dell doesnt have them on their site, perchance anyone knows where i can find one?