How employable would I be with a Chemistry PhD in the East Anglia region (Norfolk, Suffolk, Essex and Cambridge)? I'd love to do a PhD but would like to work in East Anglia afterwards. Am I making life difficult for myself? My research area would be on the Chemical Biological interface.

For a career in academia you should be prepared to be flexible about where you live. Having said that, particularly around Cambridge, there are a large number of people working in research. There are more jobs in biology than chemistry, but as you're working between the two it should give you a lot of opportunities.