Yep, normally they come with the mobo, if your stuck for a few send me a mail through my trust, ive got loads of sata cables and your welcome to a few mate
I would get in touch with OCUK, according to ASUS website you should get the following
User's manual
1 x I/O Shield
1 x UltraDMA 133/100/66 cable
4 x SATA cable(s)
1 x Q-Connector
Did you buy B grade or new?