hi dean
if you go to paypals website and click on merchant services it's all onthere, basically you just create a button there are step by step instructions(easy to do) and then copy and paste the html code into your website(someone did that bit for me),
i had a personal account with them already and just changed it to business account, there are a couple of security checks they do it was an automated phone call and then had to enter a 4 digit code they provide you with before hand.
hope that helps any probs let me know..