How to use IndexOf() method of List<object>

int index = employeeList.FindIndex(employee => employee.LastName.Equals(somename, StringComparison.Ordinal));

Edit: Without lambdas for C# 2.0 (the original doesn't use LINQ or any .NET 3+ features, just the lambda syntax in C# 3.0):

int index = employeeList.FindIndex(
    delegate(Employee employee)
    {
        return employee.LastName.Equals(somename, StringComparison.Ordinal);
    });

public int FindIndex(Predicate<T> match);

Using lambdas:

employeeList.FindIndex(r => r.LastName.Equals("Something"));

Note:

// Returns:
//     The zero-based index of the first occurrence of an element
//     that matches the conditions defined by match, if found; 
//     otherwise, –1.

you can do this through override Equals method

class Employee
    {
        string _name;
        string _last;
        double _val;
        public Employee(string name, string last, double  val)
        {
            _name = name;
            _last = last;
            _val = val;
        }
        public override bool Equals(object obj)
        {
            Employee e = obj as Employee;
            return e._name == _name;
        }
    }