I bought a Linksys SPA-1001 VoIP adapter, on the advice of one of my readers who knows a lot about this kind of thing.
I wanted to use it to access a ham-radio VoIP PBX, so that I could send and receive telephone calls from other hams, and if it worked right, maybe pay him to call outside the pbx, too.
I couldn't get it going. There are a million options to think of, and the ham who runs it doesn't have any help files or info for an adapter like mine. There are some "preferred" adapters listed on the website, and I could have bought one made by Cisco for about ten dollars more, but I didn't know that at the time.
I decided to do an end run. My reader had also recommended a company named "Callcentric," and I went and signed up with them, getting outgoing and incoming calls for about $6/month. In comparison, Frontier (my local phone company) charges over $50/month, and while I would prefer a good old 'Mericun copper pair for my phone, I'm not disposed to subsidize tradition to the tune of $44 per month.
Callcentric's website showed all their offerings, made it easy to pick an outgoing and an incoming plan - they don't force you to do both if you don't want to - and provided a very helpful "Frequently Asked Questions" document. The FAQ had me up and running within a half-hour, and tomorrow or the next day, I'll have a local phone number to use when I want to call my wife, since she never keeps a cell phone in her pocket while at home.
I'll copy the Callcentric setup over to the other "Line" in the SPA-1001 unit, and see if I can get to the ham radio VoIP server tomorrow. It's probably just that simple, but somehow I'm surprised that the ham who went to the trouble of putting a free Asterisk server up for any other ham to use didn't also take time to find out the options for every possible VoIP adapter.
Kind of sad, I know. My dad used to ask me if I wanted the world with a string around it, and one day I said "Yeah!", and he clipped the back of my head like they do on some TV shows.
I'll pay it forward, and put out a "howto" that the PBX guy can give out if he wants to. At least I won't feel like such a jerk after that.