[hexanite]

Hi, I'm trying to make concentrated nitric and was wondering what the best way to accomplish this would be.  Here is what I did the first time:
1.  Obtained ~30% concentrated sulfuric acid
2.  Boiled the water out of the solution.  I have not yet tested the concentration of this acid, but I'm assuming it's 95%+
3.  Mixed 200g KNO3 with 106mL of the acid in a flask, connected to a graham condenser.  I have a liebig one too, but it didn't seem to cool off the fumes fast enough for it to condense because there was a lot of nitric acid fumes escaping from it.
4.  Distilled
The acid came out very colored and according to http://www.chemicalforums.com/index.php?topic=9198.0, it is very impure. They suggested using a 60% concentration of sulfuric acid to make a less concentrated solution of nitric acid, but I was wondering how I could then concentrate the nitric acid.  I read that I could use sulfuric acid as a dehydrating acid, but I don't really understand how this works and was wondering if someone could explain.

[Zyklonb]

1.  Obtained ~30% concentrated sulfuric acid
2.  Boiled the water out of the solution.  I have not yet tested the concentration of this acid, but I'm assuming it's 95%+

Don't assume. Know. Did you boil it until dense white fumes where coming off? They start at around 85-90% so if not, you don't have very concentrated acid.
200 grams of potassium nitrate is nearly two moles. 106 mL of 98% sulfuric acid is 193 grams, or 1.98 moles. So, you did the calculations correctly if you assume that the potassium bisulfate also produces a mole of nitric acid. However, this only happens at much higher temperatures, so likely your yields were cut in half.   

[Zyklonb]

Due to lack of time, I was unable to finish, now the edit function is unavailable, so I will continue here.
Sulfuric acid ionizes like this: H₂SO₄ +H₂O  H₃O⁺ + HSO₄. The resulting bisulfate ion ionized again - but to a much smaller extent: HSO₄ + H₂O  H₃O⁺ + SO₄.
Thus, with a nitrate salt: H₂SO₄(aq) + XNO₃(s/aq) → HNO₃(g) + XHSO₄(s/aq).
With considerable heating, the volatility of nitric acid over X-bisulfate causes the reaction to go further to completion. Heating to this temperature cause much decomposition to the nitric acid: 2 HNO₃ → H₂O + 2 NO₂ ¹/₂ O₂. This reaction is mostly irreversible. Some of the NO₂ might dissolve in the nitric acid, but it won't be oxidized to the ⁺⁵ oxidation state. This acid is called RFNA or red fuming nitric acid. You can oxidize the dissolved NO₂ (or at lower temperatures, more correctly called N₂O₄) by adding concentrated hydrogen peroxide to the solution, or bubbling dry air or oxygen through it. When nitric acid is free of N₂O₄, it will become colorless, an excellent indicator.