Can 3DS MAX be used to create models for use in the game? Also, can Mudbox be used to model things too?

3DS Max can be used to create models for the game. Blender as well. But for either program, you need to use the Niftools http://sourceforge.net/projects/niftools/files/max_plugins/ in order to export models in the proper format(.NIF) for use with the game.

I'm not very familiar with Mudbox... couldn't say really. It probably doesn't have Niftools plugins for direct model exports... you might be able to bring a model created in Mudbox into 3DS Max, and export to .NIF from there. But I'm just guessing on this.

Mudbox being a sculpting app should not be used to create game mesh assets as it suffers from the same issues that all sculpting apps do -> they create meshes that are far to poly dense to be usable -> these programs are meant to create some of the specialized maps with not the actual game mesh assets.

Max, Blender, GMax all have exporters that are able to get working files exported, also any other programs that can export .obj or .3ds can be used to some extent to get meshes into a .nif by using the import feature of NifSkope.

Know of any tutorials to get the models into the game?

I don't think there's many tutorials out there... but it's not that hard to do. This is a great game to mod, especially with the help of the GECK.

Basically, using the Niftools plugin you can export any model you create from your modeling program. After that, you might need to tweak a few settings in another program called Nifskope(which opens/edits the .NIF files). The settings you need to tweak in Nifskope will vary depending on what programs you use and what you're trying to accomplish.

You also might want to create collision meshes for your models so that you can walk on it or interact with it in game more realistically. If you're a Max user, SaidenStorm has created a good tutorial on collision meshes.

Once you're .NIF file is set up properly and ready to use in game, you just have to make an entry for it in the GECK... and place it wherever you want like any other object.

That's really all there is to the basic process. If you get stuck along the way... I've found these forums are usually very helpful.

I made one for helmets
http://www.fallout3nexus.com/articles/article.php?id=248

statics would be the same, except you'd probably take into account making a colision mesh and in post export convert the root ninode to a BSFadeNode.
weapons - there is more to the node names, their linking and pivots. but essentially the same as a static.

outfits would be very similar in set up. obviously it would be skinned and probably dismemberment modifier is set up as well . and some export settings would changed- basically tick everything under the skin modifier in the export dialog.
you wouldn't have to change anything else in nifskope to get a rigged mesh to work in game. You may need to make some cosmetic changes, like tweak alpha flags and what not.

Thanks fellas