one-way sync of new directories / folders for iTunes / Windows Media

Hopefully this is posted in the right place.

I'm running Mac OS 10.6, but I figure if there's an answer to my question it will involve some FOSS Unix / Linux software.

I have two machines on a LAN. Computer A is my mac. Computer B is running Windows. I want some software that will watch some folder on A, and whenever a new sub-folder is added (at arbitrary nesting levels), that sub-folder will be copied over to B. Does anyone know if it's possible to set this up? Maybe with rsync?

I'm not afraid to get my hands dirty with some python scripting, but I have absolutely zero experience with rsync or anything like it.

For those who are curious:
The reason I want to do this is that I want my music library to reside on both computers. Computer A uses iTunes, Computer B uses Windows Media. Both of them seem to modify the metadata of files in their libraries, so a regular synchronization will result in a lot of conflicts (I tried Windows Live Sync).

I basically only add new music on computer A, and I figure that I'll almost always add an entire artist or album at a time, so there will always be a new directory. Thus my requirements.

I realize this question has nothing explicitly to do with Unix, so if somebody knows a better place to post it (even off of ars), please let me know.

Thanks
Gary