What has made a huge difference for me was switching to wearing Keen shoes. These are wider shoes, and luckily for me I can wear them to work (I'm a preschool teacher so I dress very, very casually.) I had orthodics made, but they did nothing for me. Superfeet.com has inserts that feel ok (not specifically for MN, but I got the pink ones and liked them), but honestly, I don't need them now that I exclusively wear Keens.
Workout shoes have been more of an issue, but with my everyday shoes having made such a difference, I'm fine wearing Ryka's to work out in for an hour a day.
I've also iced the area when I've had flare ups of the neuroma, but I haven't had to do that in 3 years (since I switched to Keens.)
Good luck!