Most people coming to work in Australia do not normally negotiate a salary package.
Having said that, senior staff who are being sent to Australia by their company as an expatriate to run their Australian operations normally would do so, back in their home country with management.
For skilled international talent, applying for jobs in Australia, and who are not being sent by their company, the situation is, of course, different.
Most employers will provide the relevant information on the Australian job advertisement about the salary or salary range (ie between $55,000-65,000) and any other benefits. This is necessary if the job is likely to be filled by an expatriate and accordingly they will require a visa to work in Australia.
Once someone applies for the position, they effectively are aware of the proposed salary and there is limited scope for negotiation: unless the person has some unique skills, experience, training and qualifications which place them at the top of the range, most companies will place new and untried staff that have not worked for them before, at the bottom of the range.
Of course, the market salary evidence requirements for the visa normally requires the employer to pay the person at a rate that is equivalent to that earned by an Australian doing the same work in the same company, provided it is above the minimum level for skills visas (ie $53,900). This is designed to ensure that overseas skilled workers are not being used as 'cheap labour'.
Having said this, the national minimum employment standards means that most expatriates working on 482 visas will be eligible for salary (minimum of $53,900), superannuation (9.5 per cent of salary), overtime, annual leave (normally 20 days, though in some remote locations there may be some additional days), sick leave (usually around 10 days). Many companies do provide productivity bonuses for staff that are highly productive as an incentive. It is up to the company to provide any additional benefits if they wish to do so (normally these benefits may be items that are cost effective for the company to provide).
It is also important to note that a condition of obtaining the visa, is the person must have a complying health insurance policy (this is a private responsibility, but essential otherwise the person will be deported if they do not comply).
Of course as the person continues working for the company, most will receive service increments to reflect their contribution to the company.
I placed a BMW technician with a dealership in Australia, three years ago and he commenced on $54,000: he is now on $68,500, plus around $6,000 in productivity bonuses, around $5,000 in overtime plus he receives company funded superannuation contribitions of around $6,500 per year. He and his wife obtained permanent residency earlier this year and they have just had a baby boy born a month ago (who is an Australian citizen). They are very happy with their circumstances.
As you will note, therefore there is very limited scope to negotiate a salary package, but that does not tell the whole picture.
I trust that this assists.