semigeek: Tried this?
http://www.appbrain.com/app/pinger-textfree-free-texting/com.pinger.textfree

 Actually ignore that, but I wonder if you would be able to do it with Wondershare's MobileGo. 
 http://www.wondershare.com/android-manager/


As it turns out, Wondershare MobileGo isn't able to send SMS txts from my tablet but it is a great app that I've found useful in other ways, so thanks for the recommendation. In particular it's proven the best way to connect to my network without a cable.

There are free SMS options out there but so far I have been unable to fine one that will use my HTC touch phone account on my Android tablet. I have found Red Oxygen offer an Outlook add-in which is great on my laptop but no good on my tabet.

So I have emailed Telecom for advice, since it's their network and they sell these tablets, one would expect they have a suggestion.