// create mail message object
MailMessage myMail = new MailMessage();
myMail.From = "from@youremail.com"; //the "from" address     
myMail.To = "to@theiremail.com"; //the "to" address         
myMail.Subject = "Howdy"; //your "subject"
myMail.Body = "Just wanted to say Hi. How are you?"; //message body     
SmtpMail.SmtpServer = "localhost"; //the mailserver

//send the email
SmtpMail.Send(myMail);