You guys, downloading D2 isn't the hard part. The part of D2 that costs money and the only part that you really NEED when you get banned is a new CD key...which downloading a copy won't get you. Sure, it might come with a CD key in it, but it's either going to be in use, or is a nullified key. If you want to play again, you are just going to have to chip out the extra cash and pay for it.
If you were banned from BNet and you WEREN'T using any kind of third party program, send e-mails to blizzards support team and demand an answer.