yep i would agree w what Miss E said re the diff obs, go with someone who you gel with and who has good references... (assuming you have chosen someone you are comf with). the fees do vary a lot and some of them are kind of 'trendy'... but may not be the person you want... (or may be and thats why they are popular).
i wasnt sure if the medicare safety net thing changed (it was all changing aruond when DS2 was born)