The Raspbian version with overclocking was released yesterday. Here's a link to the article: http://nerdvittles.com/?p=3026
POTS phones require a separate ATA device that converts analog signals to SIP and vice versa. The best one out there is the OBi110 which runs about $50 on Amazon. Basically, you plug your phone into the ATA and plug the ATA into your LAN. Then you connect the ATA as a SIP device to Asterisk to process incoming and outgoing calls. Here's a good article from the FreePBX folks on how to set it up using the FreePBX GUI included in Incredible PBX: http://nerd.bz/Q74uOg
You'll find loads of free help on the PIAF Forum if you get stumped: http://pbxinaflash.com/community
Good luck with your adventure!