If you want to learn, go for it. But there are many open source library management programs. I use SlimServer from SlimDevices.com. They sell hardware, wifi audio, etc. but the server itself is open source, runs on Windows, Mac and linux, and does not require their hardware.
I looked around for java ID3 tag libraries, and didn't really like any that I found.
Plus I wanted to learn about it.
So, I wrote me own, which can be found at http://www.beaglebuddy.com.
It is open source, free, provides e-mail support, has amazing javadocs, lots of sample code examples, uses java 1.6 and works on Android, Windows, Linux, Mac, etc.
In my opinion, it is 1000 times better than anything out there.
You can load mp3 files from a local file system, from a URL, from a network drive, etc.
Especially loading mp3 files from a URL, which is something I have yet to find in any other java id3 library.
It has support for synchronized lyrics (ie, making mp3 files into Karaoke songs), support for images in your mp3 files, etc.
The javadocs are excellent. I spent a lot of time on them.
The sample code gets you up in running in a few minutes.
The design of the library is also far simpler and much easier to understand than anything else I've found out there.
But, I wrote the library, so don't take my word for it.
Check it out for yourself to see just how good it is.