I made one and it works good. It took about 5 bucks worth of parts, and old stuff I had laying around. I don't have IR Track, so I can't compare.
It takes some experimenting, so if your not good at building things, you may not have good results. I bought a bag of assorted LEDs from Radio Shack (2 bucks I think). I had resistors and wire around the house. I used 4 yellow LEDs for the head set, and a 9 volt to power it.
For the frame, I thought the coat hanger was a bit cheezey looking, so I went to the hobby store and got a pack of aluminum tubing and a set of tube benders (tight wound springs that fit tightly over the tube). I made the frame per the instructions, but ran the wires in the tubes. Now I have a cheezey looking tube frame

I soldered up everthing connected the battery and it lit up fine.
I used an old web cam that was laying around gathering dust. For an IR filter, I used an exposed end of a developed 35mm film negative. Start up the Free Track software and it works. It takes a bit of tweeking of the settings to get the right feel. No problems with back light. Just adjust the setting so it only sees the LEDs.
In AH, just start up Free Track, minimize it. Start AH, and it works.
Gunner