I am a malaysian, trying to get a job in Australia (Perth)?

It depends on who you deal with. If the person is a PC lefty you just might get in otherwise it could be difficult. Generally Oz immigration policy favours Europeans and Asians. They're leary of Africans and aren't too fond of Yanks.

If you're here on a 12 month Work and Holiday visa, you're going to have trouble finding work in the tourism industry when you can only work for 6 months for any one employer. They would need to train you and are unlikely to find it worthwhile for only 6 months. How about hotel front desk work where your language skills would be useful? If you're on a tourist visa, you are not supposed to look for work and if you find something, it is illegal for you to work there and is a deportation offence for you with large fines for the employer. If you want sponsorship for a long term visa, employers can only sponsor you for occupations in which you have experience and qualifications and which are on the list below. You don't seem to meet those requirements.