Hi Jason!
Now, if your using a transform ultra, your running Gingerbread 2.3 (correct me if I'm wrong)
Here's a link to help root:
How To Root Android 2.3 Gingerbread Using GingerBreak
it seems quite easy, almost one click! just follow the steps, and you should be good.
As for the app, it's called Wireless Tether. BUT... remember that with rooting, always has the chance of bricking your phone (meaning that It can't be used anymore :-\ )
But, it's quite rare.
if you just want to use your phone as a tether, there is an app, that works WITHOUT rooting. It's called FoxFi. Just try it out, see what happens!
best of luck,
TLRTC
(The Little Robot that Could)
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