For your A level ICT I recommend studying and possibly even obtaining your Comptia A+ and Network+, if you feel confident after studying both of those you can put yourself in for the exams at a local pro metric test center and they are regarded very highly within the industry for entry level qualifications. Study to A+ and Network+ standard and you will breeze the A level ICT
http://computer.howstuffworks.com/
That is a reasonable source for information, I would use it as an ice breaker in to any topics you are looking to study as it sometiems does not offer a level of detail that is fully needed.