I use Skype for outdial calls(paid 30$/year for unlimited call in US and Canada).
I had an headset and it kinda pissed me off so I got an adaptor to use my regular PTSN phone.
http://www.dlink.ca/products/?pid=466
Might also get a DID or 2 with my PAP2+maybe asterisk and reroute it to that box so it makes transparent out calls and also receive in calls from the DIDs.