isaBook for Mac

From Malia Software:

isaBook is an easy-to-use address book that offers a powerful Filter feature. With one click you can handle a wide variety of contact information: name, address, 3 phone numbers, e-mail address, web page, and even notes! Its Filter feature allows you to find any of your contacts by typing partial information such as the last part of a last name, the name of a city, or a phone number.