Why are there more pornstar sites then others?

[woody02]

I was wondering why it is easy to find some girls on the net (Briana Banks, Jenna Haze, Gauge and Krystal Steal ect) they are all over the place but some girls (Shay Sweet, Dee, Mariah ect) are nearly impossible use this site for example click on one of the 1st names and there is hundreds of links but click the latter and there is maybe 20. I looked at the filmography and they were in lots of movies so why cant i find them? thanks