There's actually a couple options for doing custom pinball tables nowadays. The simplest program to use is Future Pinball, however, development on it stopped many years ago so even though it's easy to use, it has technical issues abound. OTOH, Visual Pinball is still in active development and is extremely powerful, with people going so far as to accurately recreate real pinball tables with it, but it's a lot harder to use.
The trouble with pinball creation software in general is that there's no simple way to allow for extreme flexibility, so any of the software out there which can do it is generally powerful but hard to use, or easy to use with fewer customization potentials.
--- Kris Asick (Gemini)
--- Pixelmusement Website: www.pixelships.com
--- Ancient DOS Games Webshow: www.pixelships.com/adg