[TCML] Inductor design program?

[jhowson4 at comcast.net]

Hello 
I am attempting to figure out how to design the Inductor for the ballast I am working on. does any one know of a program (free) that will allow to me to input the core dimensions, wire gauge, insulation thickness, number of turns etc. And tell me things like the inductance, resistance, will it fit in the core window, ect. 

I have been looking for about an hour now to no avail. 
I am trying to design the Ballast I am working on but cant really find the much info about how to do it, any suggestions. 

I was planning on winding a coil and tapping it at various points, this would allow me to have a wider variety of inductance choices and thus current choices. such a plan will probably consists of multiple coils of different gauge in series. It does not make sense to wind an entire coil with 40amp wire when only 1/4 of it would only ever be carrying 40 amps. Right? 

Thanks, 
John "Jay" Howson IV