Living at home can be frustrating. I found myself moving back into my parents home at 30, after being independent since the age of about 18. After feeling inadequate and embarrassed, I started to realise that I've been given an opportunity to 'get myself together' in a secure and safe environment.
I do realise that your situation is slightly different, in that you haven't had the chance to be independent and strike out on your own, these feelings that you have, these frustrations could lead to more serious mental health issues like depression and anxiety if you don't address them.
I would suggest that you remain focused and continue to work hard at your career choice. Your Mum will continue to be your Mum, I'm nearly 50 now and my Mum will still spoil me, tell me how to wash and cook and brush my teeth and I live in a different state entirely. This is what Mums do. And I'm 6'2, big and bearded and covered in tattoos.
As others have already written, the economic climate is tough at the moment, so if you are going to try and move out, look hard at what you are about to do and how you are going to do it. Do not put yourself into debt or make rash decisions based on being in a negative state of mind.
As awkward as it might be, stay on the positive side, focus on your job, take more TAFE (or look at Uni) courses, do some independent study i.e. get some software programming skills under your belt, create a project that you can work on, learn some new software like desktop publishing and maybe look around and volunteer for a local community project or charity that could utilise your skills. Do things that can build a portfolio of work that you can present. Make yourself more valuable in your job. Whilst you have the security of living at home, you can really grow in your skill sets, embrace it, work harder and focus.
When you are ready, the opportunity will present itself.