my friend, jim, teaches at main street.http://www.mainstreetyoga.org/
he's got classes on tues and thurs afternoon/evenings and sat ams.
edit: i see now those are just his beginner classes. he's gas a couple more intermediate ones, as well. you can pay as you go, or buy a bulk pass (at a discount) to be used up in a prescribed amount of time.
he's very calming and patient.