@maiSG03 you dont need to have a relative in SA if applying for state sponsorship unless your occupation is in their "special category" or supplementary list. If under special category or supplementary list, you either have to have high points, studied in SA, chain migration (family memeber in SA) or currently working in SA.
South Australia offers a lot of occupation in their skills list that is why it is attractive for people who wants to come over to oz. As to job, SA is a small state so don't expect too much. I agree to other posts here, it depends on the applicant if he/she wants a fancy job then it will be difficult to find one especially for new migrants. Anywhere in oz, local experience is important so I guess the technique is to get your first break in an oz company (even casual or temp jobs) and establish a local work experience.