Does your Yammie have a LCD readout? Does it have software built into it that can teach (to a certain degree)?
Even if you can't read very well, you can still develop some identification skills. You should go to the music store and find the childrens books. Some adults would refuse to pick up these books because, well, it was designed for the under 10 age group... and because they don't want to look at cartoon drawings... and their ego won't allow them to be caught using them...
Those books help with tempo, which is really important.
Also helps with note identification.