Access to free End-of-day Commodity Data

My name is Martin, I am a PhD research
student and I am currently doing research work
on predictability of currencies, stocks and
commodities.

At the moment I am collecting data for my experiments.
I only really need daily data from May-2000 untill today.

I am wondering where I could get hold of some commodity
time-series data, or for example commodity indices such
as CRB (Commodities Research Bureau), GSCI (Goldman Sachs
Commodities Indexes). I have only managed to obtain data
for RRMI (Rogers Raw Materials Index), DJ-AIG (Dow Jones-AIG
Commodities Index).

The study at the moment is non-commercial and of academic
nature. I would be gratefull if someone could help, or point me
to an appropriate resource.

greetings, Martin