Just as a heads up, while it is true that not having any/much credit history will lower your chances of getting a mortgage, there are some important things to consider.
You don't just need a credit card / loan to have built up credit history.
Most recurring payments (phone bills, gas and elec) will contribute something to your score.
You can build up your long-term credit score by getting a credit card and paying it off regularly - but if you're looking to get a mortgage in the short-term, then don't start applying for loans / credit cards. Having (or applying for) other means of borrowing now, will actually have a negative effect on your short-term chances of getting a mortgage.
I've never used noodle (above), but the main credit agencies are Experian and Equifax - but you will likely need to pay a registration fee to access your history with them.
Sites like MoneySavingExpert have some very good advice on mortgage applications and credit history.