The picture of the Bith you see below looks like it might be from the dreaded 1978 Holiday Special which included a cantina scene of another kind with friendly neighborhood bartender, Bea Arthur. I can't really determine - could go either way. My guess is it's from the film but who knows.
Also included here is an Ithorian shot. After checking the film, I can say that this particular shot of our hammerheaded friend does not appear anywhere. There's also a nice shot of those gorgeous Tonnika twins hamming it up with the bartender.
The freaky-looking green thing is an alien [later] named Kitik Keed'kak. She looks like a huge mantis. It's really just a big puppet played by Jack Purvis, according to Starwars.com.
Lastly, I just want to make a quick mention of something I read over at Starwars.com about the little rodent-looking guy named Kabe. I'll just quote the text here:
The original screenplay for A New Hope describes a trio of assailants that accost Luke at the bar. In addition to Dr. Evazan and Ponda Baba, there was to have been "an even smaller rodent-like beast." When the confrontation turns violent, the script says "the rodent is cut in two." The finished film only shows Evazan and Baba in the altercation, but careful examination of the sequence shows that Evazan is talking to Kabe before the scuffle. This indicates the idea of them being allies lasted up until shooting.
Pretty neat, eh?