To my knowledge, this is one of the most even-handed and informative websites on modern Cambodian history. It includes some oral histories, a general overview, photos, statistics, articles and links. They are generally even-handed and well written:

Cambodia: Beauty and Darkness - http://www.mekong.net/cambodia/index.htm

Other places of interest -

Cambodia Statistics:
http://www.nis.gov.kh/

Peacebuilding in Cambodia:
http://www.peacemakers.ca/research/Cambodia/

VBNK Development Resources:
http://vbnk.org/home.htm

Peace Bridges & the ICF:
http://www.icfpp.org/PeaceBridges.shtml

Silaka:
http://www.silaka.org/

Friends (Aid and Vocational training for street kids):
http://www.streetfriends.org/

Bloom Cafe and Bags:
http://www.bloomcambodia.com/
http://cambodiacalling.blogspot.com/

Riverkids Project (Stopping Child Trafficking):
http://www.riverkidsproject.org/index.html