Roughly how hard would it be to make a first person 'walker' in XNA, where you can walk around a very flat world, but if you run into a wall, you stop. Nothing else... I don't really know how hard 3d stuff in XNA is, but if anyone has any experience in this, i'd appreciate it.

"hard" is relative, depending on a lot of variables - knowledge, tools used, etc.

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Microsoft XNA MVP

Then can you link me to some good 3D XNA tutorials?

Riemers is nice http://www.riemers.net/

Also there's the official XNA tutorials and sample projects which have pretty extensive material.
samples - http://create.msdn.com/en-US/education/ ... m=0&sort=1
tutorial - http://create.msdn.com/en-US/education/ ... ng_started (seems to have changed since I last looked, which was a long time ago)

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