Does any one know how I would go adout moving to the USA with my partner and young son, we want to start a new life and we are not sure where to start!

Start with your nearest American consulate. They can give you information about requirements, quotas etc. Yoyu can also start with this site from the US State Dept.

Immigrants to the United States (http://travel.state.gov/visa/immigrants/immigrants_1340.html)

Read uscis.gov.
Immigration isn't easy, and almost always means that relatives are helping you get here, or one of you has a vital job skill that can't be filled easily.