Angie is a character who makes a one-time appearance in the Season 2 episode titled "Firestorm".
Angie is a friend of Dominic's and ran a bar somewhere in the desert. When Eddie Donahough had too much to drink and was getting violent, she asks Dominic (who brings Hawke along) to help take Eddie home.
Location of Angie's bar
Everett, when passing a messeage to Dominic, says it is from "Angie at Four Corners". There are several places known as Four Corners in California. The most likely one is Kramer Junction, also known as Four Corners. It is the nearest one to Van Nuys and within easy driving distance and it is located in the Mojave Desert, which matches the landscape shown of the exterior of her bar.