1. Answer: It depends on everyone's taste and these rankings change all the time. According to RankMyPorn, at the moment, the top ranked Caucasians Male Pornstars in the world are: Tommy Gunn, Johnny Sins, Alex Legend, Bruce Venture, Chad Rockwell, Charlie Dean, Damon Dice, Jason X, Larry Steel, Nick Ross, but these will change based on what people vote.
2. Answer: It changes. You can see the latest rankings on RankMyPorn.com and also vote on it for free.