Direct TV SCAM

I received a very professional sounding call from AT&T Direct TV offering me half off of my Direct TV monthly bill. I returned the call to 866-787-0107 and again a very professional voice led me to an "agent" with an eastern accent who processed my request. Looking back on it, the professional voice responses almost sounded like it may have been artificial. The agent knew my monthly bill amount and told me that ebay has partnered with Direct TV to create the program. I was dropped and called them back at 800-206-9438.  I was told that to get the deal I had to pay the first 6 months up front for the 2 year deal via an ebay prepaid card (OK I missed it) which I did. Now I'm out $570 and I'm angry with myself.  I just tried the 9438 number again and it's still active with multiple choices.  I didn't fall for the previous Direct TV scam about realigning the satellite but I fell for this one.

A question for AT&T and Direct TV, how did they get my AT&T phone number and know I have (soon to be had) Direct TV?