I've been investing in trackers for a number of years now and have some diversification of different types, but want to get a better understanding of which ones would be the best to buy. Just as you can research an individual stock looking at debt, p/e rations etc it seems sensible to look at these numbers for average debt, average p/e for each of the Nikkei, Dow, FTSE etc to make a decision... but how can I find this info? Anyone know a reliable source?

TIA

Rachel