Useful mostly for beginners in the wonderful world of small arms, Guns and Bullets permanently improves the Small Guns skill level. However, reading alone will not make a marksman; the higher the reader's skill in Small Guns, the smaller the skill increase will be. At very high levels, the magazine will do nothing at all. Specifically, once the skill reaches 92%, the book will cease use (this applies to all skill books in Fallout & Fallout 2). It is however possible to adjust this through the difficulty setting, or by temporarily lowering one's SPECIAL attributes (and the corresponding skills) through drug use.
In the left-hand room second from the bottom, on the upper right hand shelves. Use alcohol to lower the bald thug's perception by 9, then use Sneak to get the book.
There is one on the collapsed shelves in Eldridge's quarters. You need to injure the dog enough to cause it to flee, or kill the dog, to get to it. Eldridge also rarely sells them.