I’m with briar hill midwives and love them. You can just fill out the applications and don’t need a referral at all
I filled out the midwife request form when I found out I was pregnant. https://www.alberta-midwives.ca/. But while I waited to hear back I saw my family dr first. He gave me the requisition for the dating ultrasound so I could get things going but I did tell him I wanted a midwife if possible. Once I got accepted with a midwife group my prenatal care was completely transferred to the mw. I'm 20 weeks and this is my first baby in Alberta but so far having a great experience with Birth Partnership. I've had a few friends go with them before and they've all had good things to say
You can contact midwife directly, there is no need to get a referral. Also there is a website from AHS that you can fill up your first three options for midwife, but I suggest you to contact the clinics directly