How To Make iTunes Put Files Where I Want Them

I know this is supposed to be a simple entry in iTunes Preferences, but it defeats me every time. I want iTunes content to be stored on a Airport Extreme network drive, accessible via Home Sharing. After much fussing around, I got that working, and could verify it by looking at the content via the Finder,a dn the preference settings.

Over time, I have acquired some content when I'm not on my home network, or when the network drive was not mounted, and I decided to move it all to the network drive. To do so, I used File > Library > Organize Library > Consolidate Files. According to the decsription, this should copy media files used by iTunes to the iTunes Media Folder (on the network drive). I made sure the network drive was mounted, and clicked OK. iTunes prepared a copy, and then copied.

Rather than copy the local content to the network drive, iTunes copied the network drive content to the local drive, and changed the preferences for iTunes Media location to the local drive. The local drive now has everything, and the network drive has only things that were there before the operation.

So, how do you tell iTunes, thanks, but the library belongs where I want it, not where you want to put it?