Hi Paul, I am tempted to ask 'how long is a piece of string?'! To attempt to answer your first question (how long to get a post-doc job), this would depend on many factors; how many papers you had produced during your PhD (lots of papers helps your 'employability'), whether you are prepared to move away from your home town or abroad (hence more opportunities for employment), whether your PhD supervisors are willing and able to employ you as a post-doc.