Oxygen Sensor

Hi, I am at high school and doing a project. I need to connect an oxygen sensor (that is quite small) to an arduino board. I am having locating such a sensor, and was wondering if anyone knew where I could purchase one. Thanks PS I am a novice so the oxygen sensor has to be quite easily attached

A SCUBA supplier?

not quite understand the question:

Have you allready chosen a sensor, or do you need advice which sensor to buy?

If you allready have a sensor, what is the type of sensor you are using? + Have you read the datasheet ? + Have you a link to a datasheet?

If you google for arduino and oxygen sensor you get many discussions how it can be done e.g. - http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1258329148/5 -