Yes OEM would be great - but it will exist in the final release (and maybe before the final release). OEM is considered to be vital technology by Oracle so they will port it. In January OEM 4.0 will ship and it will be different from the Java based version we have right now. This new version is being demonstrated at Oracle World this week and will be web-based. It looks like they rely on an Apache web server to display HTML pages. This new version will also solve the current problem with OEM sw not working thru firewalls.
This week I learned that there is an Apple forum on the Oracle OTN website. It is listed under Technologies > Platforms > Oracle. Anyone can register on OTN for free in order to use this resource. I have been told that some of the Oracle developers who worked on the Mac OS X port have been known to post answers in this forum. Since it is a developer release, it is not currently possible to obtain support thru the normal Oracle support group.
I have also seen some info in the OTN Forum for installations: Products > Database > Installation
I am also have some scripts on my own website which I hope will be helpful to you. I am in the process of updating and adding links to the rest of these scripts this week - because all of the links are not complete right now.
Here is the URL for the top level page for these scripts: