It should be pretty easy to get a referral. Most people should be able to find someone who would refer them (acquaintance, friend of friend). I already referred alumni from my school just because they reached out to me on linkedin. It's just a form to fill... After that, you never know what the recruiters will do with that. Sometimes, the person you recommended gets contacted soon after. Other times it seems recruiters skip promising candidates.
No referrals, I got contacted through LinkedIn and truth be told I had interviewed there a couple of other times in the years previous and was rejected.