re: Soundfonts

I didn't see any soundfonts in the agnula distro, it could be just me. 
Here are a couple:
ftp://ftp.personalcopy.net/pub/Unison.sf2.gz
ftp://ftp.personalcopy.net/pub/PC51f.sf2.gz
Please note the host of this site doesn't like download managers. 
Please note:
http://www.personalcopy.com/home.htm
Also do a google search appropriate to your question, and there's a few
sites that address your concern that will be very helpful regarding
getting sound to work with softsynths, rosegarden, etc.
Hope this is helpful.
-justin
ps-I can't get rosegarden to work myself, but then I don't have external
MIDI equipment.  See Rosegarden's faq.