You could do worse than to have another couple of lessons to check that it is something that you definitely want to pursue (even if you are sure now!) it is a lot of money to fork out on the basis of an hour or less in a helicopter.
If you think it is what you want to do, then you must get a class 1 medical (about £400 I think) to see if you are medically fit so that you don't potentially waste time and money later, then perhaps some aptitude testing would be a good idea (have a look at The Guild of Air Pilots and Navigators website) to check you have the ability to see it through.
Assuming all is well, then decide if you want to go for modular training or integrated training - an on going debate, but you must decide what suits you - speak to as many training schools as you can. I'm sure other people with more experience will be able to offer some pointers.
Where did you take your flying lesson? I see you live in Hatfield (I live in St. Albans). Elstree is not too far (where I'm flying from at the mo), and I know Cabair operate some helicopters from there - might be worth checking out.
As for sponsorship, I don't know of any, and I don't think you'll have any luck in the present climate - someone else might know of something though.
All the Best,
TCM