Don't you just hate it when people answer their own questions

Anyway, just in case anyone else has the same query, I had this reply from the Webuser forum:
The file that you have created, open it up in WMP and then click on library, then click on now playing in the left pane.
You will now see the title and artist in the middle window of WMP, right click on the text of the song and scroll down to Advanced Tag Editor.
A new window will pop up, from there you can change the track title, the album title and the artist.
Click APPLY then OK, then when you re launch the file you will notice the names will either read as unknown or whatever you wrote to replace the original text.
One thing I would like to make clearer is that I edited two tabs within the Advanced Tag Editor - Track Info and Artist Info.
And it's worked a treat!