I just asked my local luthier how much a set up and change of nut and saddle would cost. He said around $120, but I think that the price was a but high. So my question is - How do i change my nut and saddle and set up my guitar? Is there a way to do it my self?
There are plenty of places you can go to learn about setting up your guitar. I do believe that Frets.com is a rather popular one on these boards.

But you also have to wonder what you're getting out of the $120. There are a few locals guys in my area that charge much more than any of the local stores do, because they are the best in the area. But if you're willing to put the time in to do it right, then I encourage you to learn as much as you can about working on your instrument; I personally love it. But don't count out the work of a good luthier.
"Here I sit, beneath a lonely line."

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