Create button programably:
Button b = new Button();
b.Text = "Hello";
b.Click += new EventHandler(button_Click);
b.Location = new Point(x, y);
Controls.Add(b);
To work out the (x, y) coordinates, use the normal circle algorithm:
Y = R * Sin(A)
X = R * Cos(A)
where R is the radius,
A is the angle in degrees