C# - Twitterizer 2.2 Sending / Stuck When It Gets To Sending The Tweet?

I am working on sending twitter updates from my asp.net website. I have the authorization down but I am stuck when it gets to sending the tweet here is my code behind:

protected void btnAuth_Click(object sender, EventArgs e)
{
// add these to web.config or your preferred location
var consumerKey = ConfigurationManager.AppSettings["consumerKey"];
var consumerSecret = ConfigurationManager.AppSettings["consumerSecret"];
//If User is not valid user
if (Request.QueryString["oauth_token"] == null)
{
//Step 1: Get Request Token
OAuthTokenResponse RequestToken = OAuthUtility.GetRequestToken(consumerKey,consumerSecret);
//Step 2: Redirect User to Requested Token
Response.Redirect("http://twitter.com/oauth/authorize?oauth_token="+ RequestToken.Token);
}
else
{
//For Valid User
string Oauth_Token = Request.QueryString["oauth_token"].ToString();
var accessToken = OAuthUtility.GetAccessToken(consumerKey, consumerSecret, Oauth_Token, txtPIN.Text.Trim());
lblMessage.Text = "<b>Hello " + accessToken.ScreenName + ", Welcome to my Twitter App<b>";
lblMessage.Text += "<br/> Token: " + accessToken.Token;
lblMessage.Text += "<br/> TokenSecret: " + accessToken.TokenSecret;
lblMessage.Text += "<br/> UserId: " + accessToken.UserId;
lblMessage.Text += "<br/> VerificationString: " + accessToken.VerificationString;
}
}
protected void btnTweet_Click(object sender, EventArgs e)
{
// add these to web.config or your preferred location
var consumerKey = ConfigurationManager.AppSettings["consumerKey"];
var consumerSecret = ConfigurationManager.AppSettings["consumerSecret"];
OAuthTokens accessToken = new OAuthTokens();
accessToken.AccessToken = "xxxxxxxxxxxxxxxxxxxxxxxxxxxx";
accessToken.AccessTokenSecret = "xxxxxxxxxxxxxxxxxxxx";
accessToken.ConsumerKey = consumerKey;
accessToken.ConsumerSecret = consumerSecret;
TwitterStatus TweetStatus = new TwitterStatus();
TweetStatus.Update(accessTokens, txtTweet.Text);
}

I dont know how to get the AccessToken & AccessTokenSecret.