1. For speaker wire, I use 12 ga. wire from Parts Express. It's $22.95 for a 50' roll: www.partsexpress.com.
2. For audio interconnects, I use the Phoenix Gold ARX-610, which are just under $9 for a 1-meter cable at www.beachaudio.com. The ARX-610 has a twisted-pair conductor with a tinned copper drain and a mylar foil sheild.