Most banks will do an info pack for self-employed, as will local business links.
I have been self employed for 8 years and it really is not as difficult as it sounds. The only catch is that you need to work for at least 2 schools/clubs to genuinely qualify as self-employed...otherwise you are just participating in NI avoidance fraud. Try a search on this (and minimum wage) as I am sure it was covered on pprune a couple of years ago.