For anyone interested in learning piano accompaniment I recommend "Rhythmic Patterns" from David Sprunger at Piano Lessons Unlimited. http://www.medford.net/djsprmain/musicunlimitedhomepage/index.html. You don't need to be able to read notes for this course. He teaches various patterns based on chords. Ends with applying the patterns you learned to your own arrangements. It does start at the beginning level put quickly moves to the intermediate level. Lots of free learning and pay-per-view lessons on his website.
Starkeeper