OEF
http://us.ishares.com/product_info/fund/overview/OEF.htm?qt=OEF
OEX
http://www2.standardandpoors.com/portal/site/sp/en/us/page.topic/indices_100/2,3,2,2,0,0,0,0,0,2,1,0,0,0,0,0.html
OEF is an ETF, with stock-like pricing, liquidity, and payable dividends.
OEX is an S&P index...