Dear Christina,
I'm not sure what information you wanted about deafness, but my sight will
start you on your way.  There is a page on how to test your ferret, then a
page with information regarding deafness and training techniques, lastly
there is a fun behavior page.  On the site is the addie for the email
group for people with deaf ferrets.
 
Why don't you start with my site (below my name is the site for deafness),
then from there if you have any questions you may ask the FML and/or me. :)
 
Wolfy
 
Please visit:
http://www.geocities.com/wolfysluv/
for information on ferret deafness:
http://www.geocities.com/wolfysluv/deaf.html
[Posted in FML issue 3603]