Storing data into list with class

You need to add an instance of the class:

lstemail.Add(new EmailData { FirstName = "John", LastName = "Smith", Location = "Los Angeles"});

I would recommend adding a constructor to your class, however:

public class EmailData
{
    public EmailData(string firstName, string lastName, string location)
    {
        this.FirstName = firstName;
        this.LastName = lastName;
        this.Location = location;
    }
    public string FirstName{ set; get; }
    public string LastName { set; get; }
    public string Location{ set; get; }
}

This would allow you to write the addition to your list using the constructor:

lstemail.Add(new EmailData("John", "Smith", "Los Angeles"));