Brand new at a retail store they go for $99.99 lol. Gamestop also rips you off greatly. Doubt you'll find it for under $80 at a GS. IF anywhere look on amazon.com or ebay. You can find one for around $60.
You need to have a wireless network in your house or one close enough to connect to as long as you know its WEP/WPA or it's unsecure.