Contemporary translations of Greek and Roman plays are available through the Net Library.
"Roman Theatre." Image from original photograph by elbisreverri; some rights reserved under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 licence.
Search "Greek plays" or "Classical plays" , and limit to e-books to find them.
Here are a few 'classics' to get you started:
Agamemnon by 
Antigone by 