Its paid by the sex acts, like anal, DP, ATM, things that get more "depraved" pay more.
As for the reality of the porn business BBC did a great documentary on porn, like 6 parts, each an hour touching on things like a new girls experience (how much they get paid, following them to and on a job), an episode on Debby does Dallas and the AIDS shut down they had.
As for pay, a new girl will start out at 300 a film (might be 1 or 3 scenes, could take all day to shoot), keeping in mind the big names can make a lot more but that's far and few between,
There is more money in being a SP (escort) then a porn star.
If you do it right you can actual do a chick in your own porn for less then we pay girls who escort.
Realistically it comes down to how professional your set up is, camera, lighting and workers.
Girls are not likely to want to be in a porno if you are working out of some crappy basement with bad equipment, get quality equipment and spring for a nice hotel room.
As for getting the girls, then you need to contact talent companies (not likely to be any here) or try to get the girls together yourself.
The hard part is getting the girls here in Edmonton.
Now if you want to do this to make money and start a business then you need more start up then 5k, however if you just want to bang a girl on camera for your own collection, several SPs offer this service and it will only cost you around $100 more on top of their hourly fee.