This is a fairly easy and convenient way for you to practice your dictation away from the classroom. A main page gives the basic setup for each passage (clef, time signature, key signature, starting note, starting rhythmic value), a link to a sound file, and links to the answer.

Also, you might try David Loberg Code's dictation page at Western MI University. And don't forget about Singing Cells, my new "Call-and-Response Machine" for PC.