It is useful info to know about but I think I can count the amount of English friends I have on one hand that have salaries over £25k/per year. Also, the salaries are higher in London because the cost of living is higher. try and find a 2 bedroom flat to rent for under £400 that isn't a dive or in a rough area or see if £20 will be enough for a night out on the town!
Of course, if you have all kinds of degrees and dimplomas you have a step up on your starting salaries for your profession but in general, most of the positions I've seen up here (North West England) are between £12k (cashier or checkout clerk type jobs) to £14k (starting salary for admin/receptionist type jobs).
Employers can be very cheeky (as I found out with my first job when I moved here) and try to take advantage of Canadian's trusting nature, so best advice. get EVERYTHING in writing that you are being promised and don't sign anything your not 100% in agreement with. no matter what your employer tells you, you are NOT legally obliged to sign anything you don't agree with in order to retain employement and they can not dismiss you for refusing to sign something (including a contract).
Another thing to note. your employee rights in the
UK only truely kick in after you have worked at the same company full time for over a year, full protection after 3 years employment. The grey period in the first year they can basically fire you, lay you off, reduce your hours etc etc as you are assumed by employment laws to be on "probation period" during your first year of employment even if its not indicated in your employment contract, so be cautious and be picky and look out for your own interests first (but be polite about it) or employers may very well try to take advantage of you like happened in my case. Luckily everything turned out & I matched my boss at his own game, but had I not done hours of research and consulted the CAB (Citizens Advice Bureau) I could have been left with no job, no notice of termination, no letter of reference and no leaving pay package/no money because I dared to stand up for myself and my rights.