Below is code to do 301 redirect using the global.asax.cs file.
protected void Application_BeginRequest(object sender, EventArgs e)
{
string s1 = "http://somedomainname.com.au";
string sRedirect = "http://www.somedomainname.com.au";
if (HttpContext.Current.Request.Url.ToString().ToLower().Contains(s1))
{
string sNewPage = Request.Url.ToString().ToLower().Replace(s1, sRedirect);
Response.Clear();
Response.Status = "301 Moved Permanently";
Response.AddHeader("Location", sNewPage);
Response.End();
}
THEN REPEAT FOR EACH REDIRECT YOU WANT TO CREATE
}