Also, you could just use an existing RCA interconnect that you have around the house if it's long enough. You can get RCA interconnects at a number of stores.
As BoredSysAdmin pointed out, Monoprice is a good place to shop, and it's also a good place to help you get a feel for how much these cables should cost. If they have one for $5, then you know that paying $60 for one is too much.