For some reason I am not able to post in the Logging forum, so I hope you will notice this post in the sawmill forum.
I have also been looking into log haulers. It seems all of the ones that fit the bill for what you and I are looking for are 20k or more. I recently stumbled upon a University study entitled "Applications of Small-scale Forest Harvesting Equipment in the United States and Canada". Tables in the back of the article have a fairly comprehensive list of manufacturers, capacities, and cost(a few items don't have price) of skidders, trailers, and loaders/cranes for small-scale use. It also list the distributors websites if they have one. I found this info to very handy. I will post the link below.
While I still have a while to make my decision as to what to buy, I am currently thinking that the way to go will be to purchase the loader unit seperately and take it to a competent custom trailer maunfacturer and have them put it on a Goosneck trailer. I am not sure what will be required to get this DOT approved if anything. While I really don't know, it seems to me if I can buy a loader for 10k and a nice gooseneck for 4-5k it should be able to be mounted for alot less than what a Wheeler(25k I think) will cost. If you find something that fits the bill before I do please let me know.
http://www.cnr.umn.edu/FR/publications/staffpapers/harvequi.pdf