The Vitae website is written for researchers and has a really good section on careers.
According to the UK Postgraduate Research Experience Survey most doctoral researchers cite a career-related reason for their choice to undertake a doctorate. Contrary to some expectations, research into doctoral graduate careers shows that the majority of people who gain a doctoral degree enter career sectors outside academia. In addition, a significant proportion of people starting a doctorate do not have a firm idea of what they want to do as a career.
This post gets you thinking about some of the reasons for – and against – a PhD and busts a few myths along the way. Read more here