I think you’re not understanding how this technology works which is a problem. It’s not as easy as you’re hoping and at the moment, the transmitters are large if you want to go beyond 1024x768 resolution.
To be able to send a high resolution image you need a lot of bandwidth and video takes up even more bandwidth.
For whatever reason, you have a very limited choice when it comes to things that you can plug into a D-sub connector to send video, as most of the solutions out there rely on a proprietary USB dongle. As you said, all the dongles seem to be Windows only as well.
Most other solutions will be like the one from Asus, two large things for fairly short distances, as at full HD you’re at the moment stuck with a fairly limited range that you can send the signal.
There are new things coming, but we’re not there yet, although hopefully some more things should be out by the end of the year. There are a few competing standard for wireless HDMI, but neither has really taken off as yet.
I guess you could try contacting this company goodway.com.tw they do wireless USB to D-sub adapters, but no Mac support that I can see. Maybe you can convince them to do add Mac support for you…
This thing might actually do the trick, but it seems a bit out of date with 802.11g Wi-Fi paradigm.com.tw/PE_DigitalHome_PTI-5020.html
This one from ViewSonic might actually be something you can get hold of viewsonic.com/products/projectors/wpg350.htm