Normally it should not be necessary to search for a merchant's affiliate program, as simply clicking their sign-up link should automatically join your account to their program. Sometimes browser settings can interfere with this, in which case you'd simply click their link again and sign into the E-junkie account you'd already registered.
At any rate, it looks like this may be the page you want:
http://www.rssbomber.com/get-paid.html