Custom BBcode that returns query results

[markp_2000]

I would like to have a custom BBcode that returns the results of a query.

For example - I have a list of songs in an external database. I would like to be able to have a tag - [music]Girls[/music] - query a database and return the number of songs that have the words Girls in the title.

It would display Girls - (10) where 10 is the results of the query.

Where would the hook fire?
How would I capture or scan the post?

Mark