Hello josh,
I am not an expert but will try and answer your questions.
"How much are private pilots license's?"
When i was doing mine 2/3 years ago it was approx £5000
"How much is commercial pilot licence?"
I am not entirely sure, but to get an Air transport pilots licence it can cost in excess of £50,000
"If i dont get a CPL but get a PPL would an airline doing sponsorship accept me?"
There are some companies (two that i know of) that do this kind of sponsorship. They require you to have a PPL and they train you up and in return you work for them for a set amount of time. (just google something like pilot cadet scheme)
Are there many airlines doing sponorships?
Very few airlines doing 100% sponsorship at the moment in the UK, most require you to atleast pay part of the training. but check out the threads in this forum they'll tell you all you need to know
Are sponsorships hard to come across?
at the moment, yes
and check out the replies to your last post, a few people have posted some good information about cadet schemes there.