Some of the best advice that I have ever had regarding personal/people skills was picked up from a seminar presented by Shawna Shuh. From speaking to others, voice mail, e-mail, and dressing for success, Shawna really makes great points on how to present your best self.
For example, the very notion that the way that you dress is a gift to others rather than being about yourself is a refreshing way to look at something simple like your own wardrobe and use of it.
Maximizing the effectiveness of your voice mail messages, both the ones that you leave and the message on your own machine, is another avenue for increased personal growth and success.