Assuming you want dive-y restaurants, and not bars, see:
Thi's reviews of half the noodle houses in Thai-town. Some have moved; most are still there, or can be found by a little digging around.
in Glendale, there's Elena's, Chicken Al Wazir, and a half-dozen places, all called "something-Kabob-something" which I haven't tried.
in Eagle Rock, they're all being gentrified, but there are still some.
La Parrilla. The Mexican place at Sunset and Douglas.
A couple of other spots that might be what you are looking for. Yuca's is a true dive with excellent grilled carne asada, machacha, carnitas and cochinita pibil.
2056 Hillhurst Ave (Cross Street: Ambrose Avenue)
Los Angeles, CA 90027-2719
And Dino's on Pico Blvd. in the Pico-Union district for their chicken manaico plate. $5 for a half chicken, fries soaked in the manaico sauce and some tortillas to wrap it up in.
2575 W Pico Blvd
Los Angeles, CA · More Locations
Phone: (213) 380-3554
My favorite dives:
J & J Shanghai (aka Jin Jian)
301 W. Valley Blvd. #109
San Gabriel, CA 91776
1019 N Broadway
Los Angeles, CA 90012
(not exactly a dive but very casual and inexpensive, great place for breakfast)
Rutt's Hawaiian Cafe
12114 Washington Blvd.
Los Angeles, CA 90066
Tacomiendo has great taqueria items and other Mexican dishes. And the tortillas they use for the tacos are made fresh - you'll see them being pressed as you make your order. I know of two locations: Inglewood Blvd, just south of Culver, and on Gateway, about a half block east of Barrington.