Web Forms :: Email With More Than Body (Textbox / Drop Down List)

I have a working email form in VB.NET but I want to create a form that receives more than just plain text for the body. I need it to take from more than one text box and drop down list and apply it to the body section.

Imports System.Net.Mail
Partial Class _Default
Inherits System.Web.UI.Page
Protected Sub Button_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim mail As MailMessage = New MailMessage()
mail.To.Add(email@email.com)
mail.From = New MailAddress(fromaddress.Text)
mail.Subject = textsubject.text
mail.Body = msg.Text
mail.IsBodyHtml = True
Dim smtp As SmtpClient = New SmtpClient()
smtp.Host = "host here"
smtp.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network
smtp.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials
smtp.Send(mail)
answer.text = "Thank you for your participation in my Dissertation research"
End Sub
End Class

Currently I have this:
Email:
<asp:textbox id="fromaddress" runat="server" /><br /><br />
The subject:
<asp:textbox id="textsubject" runat="server"/><br /><br />
Enter your message:<br />
<asp:textbox id="msg" runat="server" textmode="multiline" columns="35" rows="8"/><br />
<asp:button ID="Button1" text="Send" onclick="Button_Click" runat="server"/><br />
<asp:label id="answer" runat="server" /> </asp:Content>