One trick I have found to organize my contact list is to use the last name to clump like contacts together.  For these contacts, I put their full name into the “first name” field and “group” into the last name field. 

Some example groups: Contractor, DNA, Dr, Dr-call, Eat, Text

Btw, for carry-out restaurants (under Eat), I add our common orders in the notes field.  Be sure to include the URL for menus if they have a website.