OrderBy

var persons = new[] 
{
    new {Id = 1, Name = "Foo"},
    new {Id = 2, Name = "Bar"},
    new {Id = 3, Name = "Fizz"},
    new {Id = 4, Name = "Buzz"}
};

var personsSortedByName = persons.OrderBy(p => p.Name);

Console.WriteLine(string.Join(",", personsSortedByName.Select(p => p.Id).ToArray()));

//2,4,3,1