Absolutely Terrible.

  I ordered AT&T through DirectTV bundles when I ordered satellite service. The sales rep at DirectTV told me the internet would cost 19.95 a month for slow ass 1.5meg service but I decided to go ahead and get it anyways. When transferred over to the "bundles group" aka AT&T sales, they told me their 1.5 meg service was going to be 39.95 a month but I would get a $10 a month rebate off of my Satellite bill. When I asked what happened to the 19.95 a month rate they claimed they had no idea what I was talking about and they said the DirectTV sales rep had no idea what he was talking about. Can you say bait and switch?
  So I decide to go through with it as I am kind of stuck at this point and they know it. The first installation date is a week away. I take the day off, sit there all day and no one shows up. Around 7PM I look in my email spam folder and find an email from AT&T saying they are coming in 4 more days. No one ever called me and changed the appointment and I had even called AT&T back before the install date to once again try and figure out why my rate was twice as much as I was initially quoted. No help getting my rate down but they confirmed my installation was the same day I took off from work and sat at the house all day. So my wife takes Thursday off, which was the day the email said they were going to come hook up the internet. She sits there all day, no one shows.
  Friday comes and goes and I call AT&T around 4:30PM to try and cancel the whole thing. I tell them their service sucks and no one there knows what the hell they are talking about. The lady tells me they have already been to my house and hooked up my internet. I ask her what the hell she is talking about as I don't have a modem yet and there are not even phone jacks in my house, not to mention we were there all day both days they were supposed to come. Surprised we don't have a modem, se says she will get one over nighted to us. She then sets up another install date for the following Wednesday. I kept telling her their service sucked and I wanted to cancel the whole thing but she tells me to "give it a try" and that I haven't even given it a chance yet.
  Let's rewind here. In one of my conversations with AT&T they told me I had to buy my own modem. So I out an add on craigslist and on this site for a WTB DSL Modem. I ended up buying two but that is another story. So when I talked to the lady that said she would overnight me the modem she tells me that I am supposed to get one with the service. Just another case of another AT&T associate having no idea what they are talking about.
  Back to the Friday I called AT&T and tried to cancel...It's not about 6:30PM, Friday evening and I get a call at work on my cell phone. "Hey this is _______ from AT&T and I'm at your house to hook up the internet". WHAT?!? Are you serious? I just called there bitching a couple hours ago and they said someone was coming next Wednesday! The AT&T guy was as surprised as me. So I leave work and meet him at my house. This guy was the only good part of the whole process. He asks me where I want a jack and puts one in for me. He also tested some old wires sticking up out of the floor in my kitchen and found out I could just put a jack there if I wanted. At no time did I sign anything or was I informed installation was going to cost anything. He uses one of my modems and gets me online then leaves.
  About Wednesday I get the modem they overnighted to me Friday (insert sarcasm). Then about a week after that I get my first bill. I open it up and it's $211 dollars! They charged me for the modem, overnighting me the modem, the installation, the jack he put in, some wire, and God knows what else. The whole point in switching to DirectTV and AT&T for me was to save money. With this rip off I would have to spend a couple years with them to see any savings. I called AT&T heated and was pretty much told to F off. She said if I wanted to stay with AT&T she could get rid of some of the charges for me. I told her hell no, that no one at AT&T said the same thing as anyone else so if I agreed to stay next month I'd probably get a $400 bill. I told her I would pay the $211 but i would never give AT&T another dime, ever. Furthermore if the right thing to do was to remove some of my charges then it's the right thing to do whether or not I stay with AT&T and the fact she wanted to hold that over my head let me know they are not a good company.

Overall AT&T is the worst company I have dealt with in the past 5 years, probably even worse than Sprint. DO NOT EVER THINK about getting AT&T anything!