First for a start have a look at the Handbook, and more specific here:
http://www.freebsd.org/doc/handbook/...-building.html
http://www.freebsd.org/doc/handbook/synching.html
I have never used MPD5, but a quick google returns this, but the link is a little out-dated:
http://www.mavhome.dp.ua/MPPC/
I guess you'll have to get the files first and build them since it seems they are not included in FreeBSD.
Cheers,
DNAeon