In the link posted above, its a study about whole index, which is average of all the 'companies' listed in that index. and the average of those companies suggests that the average P/E which investors used to invest 20 years ago was very low, now investors are paying more money to get the X return from that company. coming to your point to investing into particular company.. this study shows that 'good' average companies are not that cheaper any more then it was 20-30 years ago.
I personally relate this with the cheap money of US,UK and japan from last 10 years. US alone has contributed 4.3 trillion in last 4 years along, UK is buying govt debt of about 375Billion Pound and increasing. and japan wants inflation in their economy wow, I don't no whats wrong with deflation. I would love to live in a country with deflation. and ofcourse the near 0% interest rates of west.
I also believe that the increase in the real estate and gold between 2000- today is type of inflation which will not result in anything good for the general poor in any ways. what if housing market collapse for second time from today? (student loan, rent ratio of general population)
anyways, It is a specialty of value investor to pic dirt poor companies with great potential and they succeed majority of the times. but and finding value will be harder with the increase in average P/E of the index. when every thing is expensive, then the least expensive thing is termed as cheap. this is the policy which we have to adapt if prof shiller is right with his study.
Ben Inker, co-head of the asset-allocation team at Boston-based money management firm GMO, which has $119 billion in assets, likens the market to a leaf in a hurricane.
“You have no idea where the leaf will be a minute or an hour from now,” he says. “But eventually gravity will win out and it will land on the ground.”