2 part question
 

2005 Dodge 5.9L
My Turbo went out. So I know I need to replace it.
suggestions on what to go with?
Im not looking to build a racer, but I would not mind more power. Better gas mileage would be nice as well.

On that same line, I would like to build the truck up little by little (I dont have much money to spend at once). What should I upgrade in order.
I read head studs would be a good start.

This question most likely has been asked before. I did a quick search and could not find it.
Please put a link, or answer.

First off, are you going to do any towing with your truck?
second, i would recommend filling out your signature so people know what you've done to your truck when people try and help out with diagnosis.
I would recommend gauges for your rig.
At least an egt gauge, one of the most important gauges you should have.
And if you have an auto tranny, a tranny temp gauge, and a fuel pressure gauge.
I wouldn't worry about the head studs right now until you get to the point of around the 500hp area.

2005 Dodge 3500, 5.9L Cummins, Standard Tranny, no mods
yes I plan on doin some towing.