Hi Skidrow,
Welcome to the forum 
I don't think you really need to book in advance if you aren't going to visit the museum during a temporary exhibition.
Nevertheless these are the contact info of the Accademia Museum in Florence:
phone:  0039 055 2388612
Fax: 0039 055 2388764
E-mail: galleriaaccademia@polomuseale.firenze.it
galleriaaccademia.collezionecherubini@polomuseale.firenze.it

For info and bookings 
Firenze Musei, phone: 055 294883
booking charge: € 3,00
Hope this helps, enjoy your visit.