I've ordered a few books and things from Amazon to help supplement what I am learning in class. I haven't really started using these extra resources yet. When I do I'll let you know how it goes... :-)
I got this English-Yiddish dictionary. It seems pretty complete. The syllables/letters that are stressed have a mark on them. It makes reading kind of difficult for me but maybe that will work well for you. Also, keep in mind it's an English-Yiddish dictionary (it lists English words and gives the Yiddish word that matches it). I will have to find a Yiddish-English dictionary so I can figure out what unknown Yiddish words mean.