Ok, I had to jump onto this one :P
The only other way I can think to do this other then VB would be to do as Dudelive said VLOOKUP. Which does make a perty long if statement but does work.
such as for the processors
=IF(A3=A11,VLOOKUP(B3,A18:B30,2,FALSE)*C3,IF(A3=A12,VLOOKUP(B3,D18:E23,2,FALSE)*C3,IF(A3=A13,VLOOKUP(B3,G18:H31,2,FALSE)*C3,IF(A3=A14,VLOOKUP(B3,J18:K27,2,FALSE)*C3,"Not Found"))))
But here ya go, I put it together on the one you posted for us to mess wit

You will notice that when you change the main item, such as processor brand the price gives you a N/A till you change the processor speed to something that corresponds with the processor chosen. I dont know how to get around that, but it does work
