Am not sure if these are any good but I may as well post them here.
I was in my local Currys in Liverpool Church Street and saw these.
DJ Hero 1 for the PS3 (comes with the deck) £24.48
DH Hero 1 for Wii (comes with deck) £19.48
Guitar Hero 5 Xbox 360 (comes with Guitar) £29.48.
These can be found cheaper pre owned but I think these are the cheapest brand new.