orbit of figure eight 3 or more bodies

If I wanted to set up some initial conditions for a 3 body figure eight orbit, what would I have to set the position and velocity vectors?

Say I have three vector inputs:
initial position <x,y>
initial velocity <x,y>
mass of bodies <m1,m2,m3>

The solutions for position use
f=mi*x''
f=SUM(mi*mj*r/|r|^2)

and equating the two to get a differential equation.

Hope this make sense.

See this for a reference of what I am trying to do:
http://www.ams.org/samplings/feature.../fcarc-orbits3