Just as an extra thought.
I've just statred using winamp and IMO it's a lot better than windows media player. I have a library of about 7k tracks, and have added them all to one big playlist, listening through and deleting what I don't like.
Some of the music I've found I don't have names for, ie, it will just say " Track 2 - Unknown author ". In winamp you can select a track ( or many ), and select send to - Auto tag. This looks up online ( A bit like shazam for phones ), what track it is, and will automatically insert all of the tags for you.
Of course, if it's music you've actually created yourself, there won't be any tag, but for 99% of the tracks i've had as unknown and used it on, it's downloaded all the tags instantly for the music and actually edited the file, that way, if you run it in anything else such as windows media player or iTunes, it will know the track name, title, genre, year etc.
Hope this helps, just something I found useful and that came to mind when you asked this. It's better than entering it all yourself. Also, if you use good ripping software I believe the tags should actually already be on the music anyway. ( Windows media player for me downloads all the media info from the net and puts it on when I rip a CD )