There is no over-arching governing body to issue regulations for affiliate marketing, probably because it is global in nature. In the US the FTC has a supervisory role and periodically issues rules that have some impact on affiliate marketing. Recently, for instance, it said it was going to crack down on affiliates who promoted products without using them themselves, or included clear statements about their affiliate status in all their promotional material. This seems to have had very little, if any, impact on what is being promoted as far as I can see.
Generally, therefore, if you want to become an affiliate and promote somebody's product or service, you have to form your own opinion about that person or entity. I presume that your main concern is about getting paid any commissions due to you?
For many affiliates the answer is to use Clickbank (clickbank.com), which is probably the largest and best known agency for handling both vendors and affiliates. They are completely trustworthy, controlling payments and refunds with a rod of iron. Commission payments are made like clockwork every 2 weeks and you have a great statistics package which you can use online or download as you wish. I have been with CB for nearly 3 years now and would recommend them to all affiliates.
Also don't forget the many forums for virtually any niche imaginable. The members will quickly expose unreliable or untrustworthy organizations. One of the best is the Warrior Forum (www.warriorforum.com), whose members are famous for not pulling any punches.
Hope this helps.