Hello Daphne. Welcome to SL.
I'm not sure what documentation you were reading. The way Maya is commonly used for SL purposes is in the creation of what are called "sculpted prims", or sculpties. Without getting into specifics (yet), there concepts you need to know before you begin:
1. The model must be created in a very specific way. Not just any old arbitrary model will do.
2. After the model is built, you must use a MEL script to record its shape, and export it to what's called a sculpt map (sometimes called a sculpt texture).
3. If you're interested in the "behind the scenes" tech, a sculpt map is basically a vertex displacement map. XYZ positions of sampled vertices are recorded as numerical values from 0 to 255, as referenced against the center of the object. These numbers are then stored as RGB values in a three-channel image. It's an unusual way to go, for sure, but it was fairly slick way of getting SL to do something it was never really intended to do (import mesh data) without actually having to give it new capabilities. Adrian Linden dreamed it up shortly after he was hired by LL.
4. The image format for the sculpt map can be any format that SL can accept, just like any other texture. These are TGA, BMP, PNG, and JPEG (JPEG is strongly not recommended).
5. Whatever you do, do NOT expect to be able to use sculpties for everything you build. They're very useful, but the majority of your objects in SL should be made out of regular prims. Sculpties take longer to download, and thus longer to appear on-screen (to rez) than do regular prims, and their poly counts are pretty high for what they are (2048 each). They must be used sparingly.
6. Master the in-world building tools first. They're far more powerful than they seem at first. You just need to get used to them. Think about sculpties only after you've done that.
To learn more about sculpties, I recommend you read through the sculpty wiki. wiki.secondlife.com/wiki/Sculpted_Prims After that, if there's anything you don't understand, come on back here and ask away.
As for animations, let's make sure we're talking about the same thing. You cannot animate models in SL, at least not the way you're probably thinking. When people talk about "animations", they usually mean poses and movements for avatars. Most people use Poser or DAZ|Studio for this, since they come set up for it right out of the box. But you can use Maya if you prefer. You'll need Orion Neville's rig, which you should be able to find over on the animation forum, or you can make your own if you really want to.
So you know, the animation format is BVH (Biovision heirarchy). It's a text-based format for describing bone structure and movement, primarily used by motion capture systems. By default, Maya can read it, but not write it (since the expectation is the mocap system would be doing the writing, and Maya would just be importing from there). In order to get Maya to write to BVH, you need a MEL script. One comes with the aforementioned rig, or you can also find it separately on the animation forum, or you can write your own if you're so inclined.