Answer:
   
   All four are found within the 5 books of Moses.
    1. The wise son's question is from Deut 6.
    2. The wicked son's quesiton is in Exodus 12.
    3. The simple son's question comes from Exodus 13.
    4. The answer we offer the unasked question of the one who doesn't
       know to ask is provided in Exod 13 as well.
       
   Much ink has been spent on why the answers given the wise and wicked
   sons in the Torah are not the ones used in the Passover Haggadah. The
   Torah answers the wise son, "We were slaves to Pharoah in Egypt', a
   text used earlier in the Passover Haggadah. The Haggadah, here
   continues that answer from the theoretical to the pragmatic, and
   therefore has you telling the son all the laws of the evening. The
   Torah's wicked son differs from the Haggadah. The wicked son asks,
   "What is this work for you?" The Torah states that this son is of a
   generation who grew "old in the land", whose parents go through the
   routine, but really see it as work. The harsh answer of the Haggadah
   is therefore not given the Torah's version of the question--its child
   is not fully accountable for its attitude.
   
   Note that in Pesachim 116a we find four questions more suited for when
   the Temple is standing: one about matzah, maror, roasted lamb (the
   qorban pesach) and abut dipping twice. Today, without the qorban, that
   question became moot. However, reclining is out of place; it's both no
   longer in style, and not the norm for a people still struggling to
   return. Therefore asking about it was a logical replacement. And, the
   Vilna Gaon writes, this preserves the parallel in number to the four
   cups of wine and four foremothers. The Rambam (Hilchos Chameitz
   uMatzah 8:2-3), on the other hand, writes that there were originally
   five questions. The one about roasting was dropped, not replaced. In
   the Yerushalmi's version of the mishnah and the one found printed with
   the Rif's and Rosh's commentaries in the back of the Vilna edition of
   the Talmud, there are only three questions: dipping, matzah and
   roasted meat. R' Menachem Kasher (Haggadah Sheleimah) cites 9
   manuscripts of the mishnah, of which 8 only had these three questions.
   In all probability, this was because the maror was one of the items
   dipped. It was not felt to warrant a second question once the one
   about dipping was raised. While on the subject of Pesachim 116a, it's
   interesting to note that the rest of the "Maggid" portion of the
   haggadah appears to be a fulfilment of the mitzvah according to each
   of three different opinions. Rav has us focussing on the spiritual
   redemption ("Originally we were idolaters...") Shemu'el, on the
   physical one ("We were slaves to Pharoah...") Rabban Gamli'el, on the
   mitzvos of the night ("Anyone who did not discuss these three
   things...")