This threads got some age behind it. Hope this helps.
I used to be in the auto detail business many moons ago. We had a carpet extactor which worked wonders but the pricetag was $$$. Since I'm not in the business anymore and i still love to keep my TB looking like new I found any household carpet cleaner works fine. I have the bissell "pet stain edition" which is no more than a regular steam cleaner with a few pet tools added on. I just use the bissell cleaning solution in the machine and fire her up. If you have really stubborn areas, you could pretreat the stains with any carpet cleaner found at pepboys. Just follow the directions and then follow up with the steam cleaner to finish the rest of the carpets. Also, the steam cleaners are safe to use on headliners. Just dont soak the headliner. Clean like you would the carpets and you'llbe shocked how dirty the headliner really was.
Hope this helps,