Im having really big problems with getting AI to work in our entry. My maths is really lacking so here is a plea for help from you smart people.

I'm trying to make my AI look at the player but what ever i try wont work. I have 2 vectors, Player and AI position. currently im 0ing out the Y components (i only want to work in 2D for the steering) and normalizing the 2 vectors.
then i get the cross product between the 2 and then the cross product between that result and the AI. then i get the dot product between the last cross product and the AI. i think im missing something but i dont know what

Code:
  T := AffineVectorMake(Tank.Matrix[3]);
  T[1] := 0;
  U := AffineVectorMake(GUserTank.Matrix[3]);
  U[1] := 0;

  VectorNormalize(T);
  VectorNormalize(U);

  Cross := VectorCrossProduct(T, U);
  Cross := VectorCrossProduct(Cross, T);

  Dot := VectorDotProduct(Cross, T);

  if Dot > 0 then
    Tank.Steer := 1 // steer 1 = turn left
  else
    Tank.Steer := -1; // steer -1 = turn right
if i cant get this going then the competition entry will just be the player driving around hitting static targets (and how boring will that be!)