It seems like Sheldon Brown would just visually sight the chainline and change rear hub spacers or BB axle if necessary. You may need to just experiment.
http://www.sheldonbrown.com/fixed-co...html#chainline
See if there is a bike rescue nearby with part bins, or maybe your LBS will let you try a few out to find the right length. You can then swap for or purchase the proper BB axle.