Hi
We nearly used an agent, but my wife spent a few hours looking through the stuff on
Department of Immigration and Citizenship and realised that it is actually quite easy. The visa you are applying for is fairly straightforward as well so shouldn't be too many complications.
What I would recommend spending a night or 2 looking at that web site. It is quite a structured site so you have to go through each page picking the valid option for you. The actual application form is really the thing that tells you what you need to submit, but there is also a checklist on the site.
I don't know if you have started the process yet, but what you have to do is:
1. Do the points test on the web site to find out if you are eligable (I guess you already have).
2. Submit your skills assessment to the relevant body (again, details on the site).
3. Once the skills assessment comes back you can submit your visa application.
4. Then you will be asked for medicals and police checks.
And that's it.
The application forms do change regularly, so make sure you fill them out and send them quickly otherwise you may find that by the time you post them they are out of date.
You will be asked for evidence of skills, marriage certs, passports, etc, etc, but it is very clear what you need to send once you start looking into it. As long as you double check everything before you send it you will be ok.
If you have more questions after you have looked at the site just post it up here and someone WILL know the answer!