Yes, many. On college invasion 7, two college girls who are clearly amateurs get in on a lesbian scene with one of the pornstars. Same in vol 6, where a college girls gets some embarassed oral. In 12 a girl gets very involved, to the point where it becomes suspicious that it may have been a contrivance. That's all I know of.
In public disgrace there's a great bunch of girls getting involved in all the Steve Holmes Spanish scenes. Also in 'theupperfloor' a female member of public gets involved in 'Gemini Debauchery' where she asks a male talent for his autograph 'on the back of her throat' and then he face fucks her. she's in the background of at least one other scene on Kink.com but can't seem to find more of her.
I'm not sure about College Invasion. 
