anyone know of any good ones

How about the Yahoo! Briefcase? (http://briefcase.yahoo.com) ;)

www.virginstudents.com gives you 20megs of space

you could also maybe try set a number of yahoo clubs as you are allowed to upload 20Mb of files for each club, the only prob would be you would have to convert the mp3 to a low birate , I know someone who has done this , take a look
http://groups.yahoo.com/group/justjinger/files/Eight%20songs%202001/

HTH

M_rsa

also some free hosts have bots to search for certain extensions they dont feel is apporiate. many also change or add an extension that is ok like a gif. dont know if u should worry much about this but just is a thought.