There is a site that is a great reference for BMW wheels:
http://www.bmwstylewheels.com/
It has pictures, sizes, weights, offsets, and what vehicles they came on. I use it a lot trying to find other wheels that might fit my 1 series.
So there is a size (highlighted) that came on the e46 that would fit perfectly. But I've looked for them and they are hard to find (possible more common in Europe), so I doubt you could find those.
I'm not terrible familiar what sizes and offsets can fit on a e46 so search the list yourself:
