I'm a developer for just about 6 months now, and since I enjoy programming I make a couple of little programs. I've started making encripters, calculators, tools, stuff to play with DropBox (hehe), stuff that play with bitmaps, drawing graphics, and even a program to update the MSN display image according to the artwork of the music you're listening yo on iTunes.

Now I kind of ran off ideas of programs to deal with information, and I've had an idea: play around with 3d! so I've read a little about it and figured I'd have to have good notions on position and math on point spacial position (which I do, from my 3d modelling experience), but I don't know how to use API's for it, so I've 'simulated' simple 3d with a simple program I've made (it's just a spinning cube, please, first one to open it, comment here stating that it's safe, i've got no reason to harm anyone's pc.)

One of my other hobbies is 3d modelling (completly amateur) and I'd like to mix these hobbies together!

Here are some questions:
1) What would be a nice 3d development tool for a .NET programmer like me?
2) Is there a way of using 3d models made in 3DS Max ? (I intend on modelling characters)
3) What knowledges should I have in order to render it, and move it areound ?
4) Which API should I use ?

NOTE: Not a dupe, I'm asking for directions specific for .NET development possibly using 3ds MAX, and there are no questions about it!