I've just finished reading a new book called Twitter Power by Joel Comm.
The book starts by giving a good overview of the social media landscape and then goes into detail about what Twitter is and how it can be of benefit to you.
The book then goes on to talk about how to set up your account, how to tweet, how to follow people and how to get people to follow you.
There are then different chapters on how to use Twitter to build your brand and how to use third party tools with Twitter.
If you are just starting out with Twitter then I would definitely recommend the book. Even if you have been twittering for a while now there are some useful hints and tips in the book.
Well worth a read!