PHP Count/Group By Top Occurrences Of Data In mySQL

Basically this is what I need... I already have users in a database who are each given a unique id number (1-whatever). These people refer others to my site through their id number and when they do, their id number, the name, email address of anyone they refer and datetime is also stored in the same database but in a different table. I need a way to list who has referred the most people along with the number of people they have referred. For example... If I click a button that says... "Show Me The Top 10 Referrers", the php code you write would query my database and list the top ten people who have the most number of referrals associated with their id numbers. The output should be something like... First Place: John has referred 93 people Second Place: Jane has referred 75 people Third Place: Steve has referred 73 people etc If more than one person has the exact same number of referrals, they should be given the same position. For example... First Place: John has referred 93 people Second Place: Jane has referred 75 people Third Place: Steve has referred 73 people Third Place: Jesse has referred 73 people Third Place: Tom has referred 73 people Fourth Place: Rachel has referred 71 people Fifth Place: Robin has referred 69 people etc In the example above, all of the referrers also have their email address stored in the same line as their name. I need for their names to be clickable so that I can send each of them an individual email.