CRTC has sold the do not call list to foreign scam artists and if you added your number to the list..this would explain the 000-000-0000 calls. http://www.theglobeandmail.com/servlet/story/RTGAM.20090123.wdonotcall23/BNStory/National/home

I still get way fewer calls than I did before my number was on the list, so I'm not going to knock it (besides, I'm now trying to make a living helping businesses comply with the DNC laws; I'd hate for them to be scrapped just now).  If you do get telemarketing calls from a non-exempt organization (actually, even an exempt one has to follow these rules), they have to identify themselves, who they work for, and if they work for a telemarketing firm, they have to identify the client on whose behalf they are calling, all right off the bat.  If they don't, you can report them, and you should probably just hang up, because there's a good chance they're calling from outside the country.

As for the 000-000-0000 calls, I was getting them long before DNC laws came about, and they annoy the heck out of me (one in particular - see below).  Here's an exerpt from an email a friend sent me last month, and if you get the same call, you may want to report it:

"The number shows up as 000-000-0000 on my display, but you might have
experienced this one as well...

First silence, then the loud horn that comes on and says, "This is your
Captain Speaking..."
I did some research and found them at: 412-414-3632, registered to
Sharon Robinson (Who's answering machine is full coincidently - hmm)."

The call came in to him through a softphone, so he was able to trace the IP address from which it came, and that's how he found her.