Point 1: The myth that "bodybuilders have small dicks" probably originates from the fact that some anabolic steroids do indeed inhibit sexual performance and lead to some shrinkage. But remember, not all muscular guys, not even all competition bodybuilders, take steroids.
The myth is also helped along by the politics of envy; some guys like to think "Oh well, his body is a lot better than mine, but I'm sure my dick is bigger." As if you had anything to do with how big or how small your dick turned out.
Point 2: If it bothers you that you think someone's dick is too small for your liking, that probably says more about you than about him.
People should stop referring to bodybuilders as freaks. They are normal guys, some perhaps with a bit of genetic advantage, who have chosen to make the most of what they have and develop their body to maximum potential, and even if you don't find muscles a turnon they deserve a bit of credit for that. Oh, and they are probably a lot healthier that the average, unless of course they they are dosing up on drugs to maintain the look.
Finally, for those who ARE turned on by male muscles, this site should get your hormones going:
http://anonym.to/?http://www.classicbodybuilders.com/
Those who aren't, you don't have to look.