Can I extend my Non B visa in Thailand after receiving my work permit, or do I need to exit the country to obtain a new one?

The user inquires about the process of extending a Non-B visa after obtaining a work permit while in Thailand. There are two main options: either to extend the Non-B visa at an immigration office within Thailand or to exit the country and apply for a new Non-B visa at a Thai embassy or consulate in another country such as Malaysia or Singapore. There is also a question regarding experiences of obtaining a Non-B visa at the consulate in Bali.