Douglas,
There are several ways to center the text, one of them is getting the rectangle from the page boundaries.
string text1 = "Este texto será centralizado no TOPO";
using (Font font1 = new Font("Arial", 12, FontStyle.Bold, GraphicsUnit.Point))
{
//O string format serve para formatar strings
//quanto a seu alinhamento e o proprio alinhamento da linha
StringFormat sf = new StringFormat();
sf.Alignment = StringAlignment.Center;
SolidBrush drawBrush = new SolidBrush(System.Drawing.Color.Black);
//Captura todo o retângulo dos limites da página
System.Drawing.RectangleF rect = e.PageBounds;
//Aumenta a coordenada de localização Y
rect.Y += 50;
//Desenhar texto centralizado
e.Graphics.DrawString(text1, font1, drawBrush, rect, sf);
}
As a PrintDocument property, the PageBounds property lets you capture the rectangle associated with the page border. I increased the value of the Y coordinate to be "like" a Title.