Sorry for my late entry.
Any time you see the Profile module mentioned concerning D6 and before, automatically translate that to Profile2 in D7. (Big secret: Profile is still there.)
Then you might find the Migrate module useful for this.
I can't imagine that you are talking about a huge amount of data here. I'd probably create a few manually, look at how the database stores those, and then probably write a quick little module to update the database directly. From what I remember seeing this shouldn't be difficult.
Another approach would be to simply use http://api.drupal.org/api/drupal/modules!user!user.module/function/user_save... stick the new fields into the $edit array.
Nancy
Injustice anywhere is a threat to justice everywhere. -- Dr. Martin L. King, Jr.
From: Fred Jones
OK I also thought custom code makes the most sense. But now I wonder if these should be Users instead of a staff content type. In D7 they should be extensible as entities I think. I suppose I could use http://drupal.org/project/profile2 or create fields directly on the user entity, but I don't know how to do that. Yet. :)
I see this http://drupal.org/node/993934 but I don't have Profile on my site. Nor do I see that it's a core option.