I've come across the odd point-and-shoot camera at the local charity shop from time to time, but nothing really too exciting. However, there is an 'antiques emporium' not far from me which has various folder cameras, but prices seem to be around the 20 to 30 pound mark. The only SLR I can recall in here was a Pentax MV with 50mm f/2 lens which I think was priced at £10.
The thrift stores in my area run hot and cold. A few months ago, I got a Nikon R8 Super 8mm cine camera for $25 and a Vivitar slide printer for $5. For the past few months there's been nothing but P&S cameras and overpriced box cameras.
"Panic not my child, the Great Yellow Father has your hand"--Larry Dressler
I've been lucky so far in my area. There's the usual 35mm P&S but I've been able to find a Canon EF, Pentax K1000, Olympus XA2 and a Yashica T4D Super. I go every couple of weeks or so just to see what's available and been surprised by what I've found.