Since it has been a while since I cruised to many of the truck conversion manufacturer websites, I thought I would do that and provide the links here (along with my own personal opinion on there usefulness, webmaster don't get all bent out of shape, it's just my opinion)
If I have left any out, please post them!
Show Hauler
http://www.showhauler.com(They updated the site with some new colors but dropped the huge photo gallery.

What a bad move that was)
Butler Motorcoaches
http://www.butlermotorcoaches.com(Site is gone, not sure if they are still around or not)
Dynamax
http://www.dynamaxcorp.com(Added the new Grand Sport Ultra, really refined rigs)
Easter Conversions
http://hometown.aol.com/lea9352812/(Seem to be gone)
Factory Motorhomes Incorporated
http://www.factorymotorhomes.com(The site provides no details about the company and very little about the product with no specifications. Not sure what to think about these guys)
Haulmark Motorcoaches
http://www.haulmarkmotorcoach.com/(Definitely have added some details, but still leaves a visitor wanting more)
Kibbi
http://www.kibbi.com/(Much more info as well as detailed photos of some customer rigs. But the site is real weird to navigate, might be my 19" monitor)
Kingsley Coach
http://www.kingsleycoach.com/web/index.html(Lots of new information, love that state trooper rig, but the images are cropped improperly and it really makes the site look bad)
NRC Modifications
http://www.nrcmod.com/index.html(Finally some product photos! And some real info, it's getting better)
Optima
http://www.optimatrailers.com/motorhomes/index.html(Nice site, well organized, still would like to see more pic's of built rigs)
Power House Coach
http://www.powerhousecoach.com(Not much new here, but wow! are those insanely long rigs. Like the innovations like the lateral drive to get that monster out of a jam)
Powerhouse Conversions, Inc.
http://www.powerhouseconversions.com(Looks like a smaller operation, but is adding photos of the rigs they have built, just wish there where photos of the interiors)
Transport Designs
http://www.transportdesigns.com(New updated site with a detailed build photo gallery. This site is much improved over the old one)
United Specialties (Trendsetter)
http://www.united-specialties.com(New site and new url. They can definitely loose that intro. Definitely more info than ever before, but still needs some organizational help.)
Wild Side Conversions
http://wildsidellc.com(Really like the updated site, love the big clear photos in the flash piece on the home page. Some of the other photos are a bit small and it would be nice to be able to blow those up. You have to check out the Mack Vision Horse Conversion, that thing is crazy)
06 Winnebago Vectra 40 KD
03 Jeep Liberty Renegade