Not well known, but probably one of the best:
"Cynics" by Anatoly Mariengof - not sure if it's translated.
"White Guard" by Bulgakov
http://www.amazon.com/White-Guard-Mi...0732587&sr=1-2. Same Bulgakov as Master and Margarita.
"Red Cavalry" by Isaac Babel
http://www.amazon.com/Red-Cavalry-Is...ref=pd_sim_b_8
"The Rout" by Fadeev
http://www.amazon.com/Fadeev-Russian...0732833&sr=1-2 Approved soviet view on the civil war, but still a good novel
"Spelling" by Bykov
http://www.amazon.com/Orfografiia-Sp...732945&sr=1-18 contemporary view by one of the best young Russian writers
And of course Pasternak as in the previous post