These are some of the bodies that I have used for my action figures and would recommend to others:
CooModel: CooModel makes a range of action figures mostly in the 1/6 scale department, that are relatively inexpensive and highly articulated. I haven’t had much success finding a direct supplier for these bodies, but eBay has been merciful on me. What I like about these bodies is the price which in relation to the articulation is pretty great. http://www.coomodel.com/
Hot Toys: Hot Toys makes incredibly realistic action figures for many titles, everywhere from action and superhero movies, to some video games. Beyond their face sculpts being amazing they also boast awesome highly articulated bodies.
Their “TRUETYPE” Line has a decent range of body types and skin colours. I have had more difficulties acquiring these bodies and they have generally cost me more money, but I find them to be worth it, in terms of their quality and articulation (30 points). http://www.hottoys.com.hk/productDetail.php?productID=156
Phicen: Phicen is known for it’s superb seamless bodies. These bodies have an armature underneath the skin material to allow for the flexibility as well relatively realistic skin appearance. These bodies are one of the most expensive on my list but are worth buying if you are looking to have no visible joints, what I like about these bodies is the texture of the skin, as well as the fact that there are female bodies in Phicen’s lineup. http://www.phicen.com/ProductList.asp?SortID=1&Page=3
Mattel: BVS Superman and Batman.
The same Mattel that brought you Barbie also came out with a couple of dolls for the release of Batman Vs Superman. As they came out a couple years ago they are starting to become more scarce, they also cost quite a bit. The reason I figured i’d put them in here is because a lot of the ones I’ve found recently have been marked down considerably and if someone finds one for a good price it’s worth buying for the body. They generally tend to be cheaper than the Phicen and Hot Toys bodies but they might require some modifications depending on your choice of head. I like this body because the sculpt is very nice and it has double joints in the elbows and knees and has a pivotal joint in the biceps and ankles.
http://barbie.mattel.com/shop/en-us/ba/dc-universe-toys/batman-v-superman-the-dark-knight-doll-dgy04