Daz Studio. Big market of resources and models available for purchase (or torrent, if you're in a tight spot). But DS isn't for animating. It has that functionality, but it is much better if you use SFM or even better, Blender.
I know that DS and Blender are free. Not sure about SFM. But about the models, there are a lot of free ones available for download. Keep in mind that these models are done by hobbyists in their free time for no pay, so they aren't exactly the best or most versatile to use. Actually, professional animation studios spend weeks modeling and rigging (creating a model's "skeleton" to designate joints and areas of movement) their figures, depending on the complexity of the figure. Then again, I've also seen a lot of great stuff by hobbyists, so don't negate them altogether.
Regardless of what you do, the most important aspect of 3D art is the lighting. It separates amateurish work from that of the professionals. It's the difference between something like this versus something like this. I also recommend investing in an unbiased render engine (if you're not doing animation) because unbiased engines give the most realism and are easier to use to simulate real light. Daz Studio comes with 3Delight, a biased engine, and Iray, an Nvidia based unbiased engine. IRay is a bit difficult to set up, and 3Delight is rather hard to use. The best engines for Daz Studio are OctaneRender and Reality 4.2, a plugin that utilizes the Luxrender open-source engine. OctaneRender, unlike Iray, which uses the CPU and Nvidia GPU, uses Nvidia GPUs exclusively. OctaneRender allows for nearly instant renders, but use it only if you have an Nvidia GPU (I don't) and if you're willing to pay $100+ for a usage license (again, you could torrent, but I don't know how well such a software would work). Reality is much cheaper, and uses both CPU and GPU. Its render times are longer (actually, it's up to the user to cancel the render), but the good thing is that it lets you change the strength of your lights in real time. Dk if Octane does this as well, though I'm sure it should.
Have fun doing art, brah.