How to Talk to Anyone: 92 Little Tricks for Big Success in Relationships, by Leil Lowndes, is one of the most practical and rewarding self-help books I've ever read. It teaches you some small tricks that would make a big difference.
If you've read Dale Carnegie's How to Win Friends and Influence People, then you have to read this. Although Dale Carnegie's book was good, and maybe one of the best in its time, our current time is a lot different than the situation where it was written. How to Talk to Anyone is the answer, and is sort of like the updated version of the classic Carnegie. How to Talk to Anyone is more practical and the tips are easy to apply.
I suggest that for each lesson, you spend from a day to a week meditating on it and applying it in real life. This turned out quite effective for me, as it allowed time for the principles to sink in.
This is definitely a must-read book. Don't miss it.