Register at Home Page - Buddy Auth Portal (and use the same e-mail address you bought HB with), and view the "Keys" tab
Are you sure you used the same e-mail address as you did the order with? Have you been redirected to some landing-page after you entered your payment informations? If not, have you been redirected to this thread?
How long has it been since you ordered HB? It could take a few hours, even up to a day for payment to be a approved and your key sent... took like 2 hours with mine...
Trust me I understand, you want your new toy... NOW... but just be a little patient and you'll have your WoW toons doing things on their very own soon... lol
yeah it will get sorted soon i bet, so in the meanwhile... take a look around in the forum and read up on the areas where you wanna use your bot for so you get up and running as quick as possible