I guess every girls first scene is a amateur and porn star. I will say my favorite scenes are where the girl is getting professionally fucked with a big cock for the first time
On the flip side, what exactly do you consider a "pornstar"? Because Phat Zane or Johnny Dark are guys I'd consider 'popular' but not 'pornstars,' really. Most or all of the women in their videos are just regular women getting it on with 'porn stars'... You can search here for those.
There was one years ago where a rich husband paid Peter North to do his beautiful Italian wife, It was good would love to see it again if anyone can find it