Where can I purchase a (gently) used iPhone 4S for a reasonable price?

I'm finally going to cave in after years of Android phones and Blackberry battery problems. There's only so much more I can take… My whole family has iPhones (my mom recently upgraded from a 3GS to a 5 and she adores it) and the majority of my friends have them as well. I heard Game Stop sells them, but I'm not eligible for an upgrade yet so what would be my best option in terms of relatively cheap pricing? (Best Buy? Walmart?) Thanks

P.S. I love Siri! I'm tiring of using other people's phones to get my Siri Fix! LOL
<3

Added (1). They're all pretty pricy so far… However, I just got promoted. Maybe I should treat myself:?

<3

Added (2). R u an iPhone user? LOL

Your bound to come across what your looking for on eBay.

*facepalm*

Siri is the absolute WORST voice recognition service out there. Compared to Google Now, it's just some silly little toy for children. It honestly doesn't do anything.

Used iPhone 4S
Source(s):
http://www.amazon.com/...=yhs001-20