I've the Visual Studio 2008 installed on my machine(licensed one). When I try to add a new .tt(say bar.tt) file to the project, the following code is generated:

I've seen in a screencast, where in an empty .tt file should be opened and the developer enters the T4 code. Even if I remove the code and enter T4 code, am getting build errors.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Linq;
using System.Reflection;
using System.Windows.Forms;

namespace Foobar
{
    partial class bar : Form
    {
        public bar()
        {
            InitializeComponent();
            this.Text = String.Format("About {0} {0}", AssemblyTitle);
            this.labelProductName.Text = AssemblyProduct;
            this.labelVersion.Text = String.Format("Version {0} {0}", AssemblyVersion);
            this.labelCopyright.Text = AssemblyCopyright;
            this.labelCompanyName.Text = AssemblyCompany;
            this.textBoxDescription.Text = AssemblyDescription;
        }

        #region Assembly Attribute Accessors

        public string AssemblyTitle
        {
            get
            {
                object[] attributes = Assembly.GetExecutingAssembly().GetCustomAttributes(typeof(AssemblyTitleAttribute), false);
                if(attributes.Length > 0)
                {
                    AssemblyTitleAttribute titleAttribute = (AssemblyTitleAttribute)attributes[0];
                    if(titleAttribute.Title != "")
                    {
                        return titleAttribute.Title;
                    }
                }
                return System.IO.Path.GetFileNameWithoutExtension(Assembly.GetExecutingAssembly().CodeBase);
            }
        }

        public string AssemblyVersion
        {
            get
            {
                return Assembly.GetExecutingAssembly().GetName().Version.ToString();
            }
        }

        public string AssemblyDescription
        {
            get
            {
                object[] attributes = Assembly.GetExecutingAssembly().GetCustomAttributes(typeof(AssemblyDescriptionAttribute), false);
                if (attributes.Length == 0)
                {
                    return "";
                }
                return ((AssemblyDescriptionAttribute)attributes[0]).Description;
            }
        }

        public string AssemblyProduct
        {
            get
            {
                object[] attributes = Assembly.GetExecutingAssembly().GetCustomAttributes(typeof(AssemblyProductAttribute), false);
                if (attributes.Length == 0)
                {
                    return "";
                }
                return ((AssemblyProductAttribute)attributes[0]).Product;
            }
        }

        public string AssemblyCopyright
        {
            get
            {
                object[] attributes = Assembly.GetExecutingAssembly().GetCustomAttributes(typeof(AssemblyCopyrightAttribute), false);
                if (attributes.Length == 0)
                {
                    return "";
                }
                return ((AssemblyCopyrightAttribute)attributes[0]).Copyright;
            }
        }

        public string AssemblyCompany
        {
            get
            {
                object[] attributes = Assembly.GetExecutingAssembly().GetCustomAttributes(typeof(AssemblyCompanyAttribute), false);
                if (attributes.Length == 0)
                {
                    return "";
                }
                return ((AssemblyCompanyAttribute)attributes[0]).Company;
            }
        }
        #endregion
    }
}

EDIT: I didn't download any T4 software separately as I got to know that it already ships with Visual Studio 2008.