Like the title says, is there a way to edit the Sort By options for the People Search Results page. Currently the options are 'Default', 'Social Distance', and 'Name'. I'm assuming this is going to require editing, the XSL, but I don't even know what to look for in there. A link to a tutorial would be great.
Sort Options control is rendered using XSLT for Search Action Links and Core Results for People web parts. So, the preferable way to customize it using XSLT based approach.
Lets discuss how to provide additional sorting options as shown on picture below
Please follow my post about customizing People Search Results with Custom Sorting options using XSLT for more details