HELP WITH MELEXIS 90217 HALL EFFECT SENSOR

I have a Duemilanove w/ Atmega328 and i want to apply a sensor(melexis 90217) to measure magnetic field.My problem is...how much resistance and which capacitor i must apply to a breadboard?I need an adjustment circuit and please if you can show me a schematic i would appreciate it!

you're very helpfull..this datasheet helped me..and you're right..my project is to detect metal things and represent some values in my pc...i must take the analog input and make the digital conversion by programming the arduino.Then i have to represent the digital values ,somehow, with a java code(GUI) with grafical representation.(sorry for my english i'm from GREECE!)

.i must take the analog input and make the digital conversion by programming the arduino.

You can't do this with this sensor. This sensor will only give you an on or off indication. There is no analogue output to digitise.