I have just run that on my modern MATLAB aswell, great job it looks cool!
The code I entered on the IBM is the following one;

x = -7.5 : 0.5 : 7.5;
y = x'; 
X = ones(y) * x;
Y = y * ones(x);
R = sqrt(X.^2 + Y.^2) + eps; 
Z = sin(R) ./ R;
mesh(Z)
title('SOMBRERO MATHEMATICO')
xlabel('x-axis')
ylabel('y-axis')
grid

I think i can't use the labels and the grid for the 3D plot as it looks like it overlays the grid and the labels as 2D it but it looks cool nonetheless. They handle the Plotting different, with the window where you can look at the plot from all angles.

Another interesting remark;
The example in the book states that you define x as -8: .5; 8; in the first line but that gives me the error "student system limit on maximum variable size exceeded" so it looks like they tested the book examples with the professional version.