Know this: Anyone who emails you is going to be stupid because they believe something like this. So they'll probably fall for a lot of this stuff.
First, create a video saying that you found an exploit, coded it into a program or something like that, and now you are able to unban temporarily banned / permanently banned WoW accounts. Upload it onto youtube.
Put comments as approve only and promote it.
At the end of the video, tell them to send their Account name and e-mail that the account was registered to to one of your emails, but tell them not to give you their password. There'll be little suspicion because you didn't ask for it or the secret question / answer. Tell them to include why their account was banned, and whether or not it was a temp ban / permannet ban.
Now, wait and you should get a lot of emails. (You really want temp banned accounts).
Now, if the account temporarily banned, then this is ideal. (Temp bans are annoying, especially if you miss a guild raid or event, so you may get more emails than you think about temp bans).
First, email them back and say you need more information to unban their account. Make up some bullshit excuse like thier account made a major offense, and you have to authorize the unban and you need their secret question. That's all. Just their secret question. Hopefully they'll give it to you.
Then, spoof an email acting as a blizzard employee. Email their account saying there was suspicious activity involving the account that involved exploits and hacking and that they have a chance of getting permanently banned, and the person will believe it and assume that you messed up / lied and now their account may be permanently banned. Say that the hacking attempts were all logged and they were by a different IP, so they know it was by someone else (you).
In the blizzard email you send, refer to them by their account name, and don't ask for their password, and remind them that blizzard will never ask for his or her wow account's password. This'll help persuade the person that the email is legit blizzard.
Say that you, the blizzard employee, have to confirm that their WoW account was not hacked by someone trying to get it banned. In the email, ask the person their secret question that you got when you sent the first email. Also ask them to include the normal information that you need to get their password, besides the secret question, account name, and email, of course.
Now you have the Secret question and answer, account name, email, and contact info. Get the pass.
As for the permanently banned accounts, you'll get A LOT of these. This scam isn't as eloquent, unfortunately.
Email them back saying that their account was banned for hacking / exploiting, and that you cannot simply run the program and get their account unbanned. Say that you need all their information to trick Blizzard and that only then can you authorize the unban. Say that you can't scam them because their account's permanently banned and there will be no point. They'll probably email you with what you want.
Now, those who were permanently banned were probably because of hacking, scamming, exploiting, botting/ powerleveling. Any of those reasons mean that the person is a WoW addict, and they probably have made a new account. Most likely, they'll use the same exact information that you got from their email.
Now you can go quite a few ways. You can wait a few days and email them again asking if they have any other accounts besides the one that got banned, and what the name is, saying that you need that info to unban the account.
But you also have their email and most of their information. You can use google and many other resources and see if any other information is linked to that account, and maybe you'll find that they have another WoW account.
Once you get their other account name, see if you can take their account by using the same information that they gave you in their email to get their pass.
Now you have an account.
Or the BETTER way is contacting Blizzard and see if they'll unban your account. You have to be smart and write well to do this. Since you have all their information, you can easily pose as the other person. If you convince Blizz to unban their account, just take it you have their info.
Note: If you don't like the perm account scam, just say in the video that you can unban temp accounts only.