Health Management Jobs Uk

What jobs are avaliable in the UK building profession?
I want to get in to the management side of things but first want to learn the grass-roots practical aspects of working on a building site.
Which jobs on a building site require no previous qualifications? Someone told me a hod carrier is the lowest ranking, so to speak, so could I just walk on to a building site after a health/ safety briefing and start work as one of these? What about a labourer or a brick layer?
I have heard you now need to take a course to be a bricklayer- if so, how long does this take and cost, roughly?
Thanks!
Laborourer,plasterer,brick layer.
UK Public Sector Management Consultancy Recruitment Update & Jobs Winter 2009 – BLT