Thanks for posting your questions.
Regarding visiting wineries that make super tuscans, the two regions that have a higher concentration and are most famous for super tuscans are the Chianti Classico area and the seaside region of Bolgheri.
Bolgheri has a high concentration of super famous wines such as Sassicaia, Ornellaia, Guado al Tasso, etc. Most of the wineries in this region only receive visitors through the Consorzio. Here's a list of wineries: http://www.bolgheridoc.com/html.aspx?page=aziende.html&id=1519
Chianti Classico also has a range of rather famous Super Tuscan wineries such as Montevertine, Riecine, Isole & Olena. Here's a list of Super Tuscans and their wineries: http://tuscany-wine.com/super_tuscans.htm. Try to contact each winery individually for an appointment.