Beginners might want to start with the following works;
1) An Introduction to Information Theory, Symbols, Signals and Noise by John R. Pierce - A classic general text to understand the concepts and build intuition. Other books by the same author are also excellent.
2) Information Theory: A Tutorial Introduction by James V. Stone - A good general introduction. The author has similar tutorial books on other subjects which are also good.
3) A Student's Guide to Coding and Information Theory by Stefan Moser and Po-ning chen - A concise guide. The other books in the "student's guide" series from cambridge are also good.