click event on .Net 3.5 please

What kind of tutorial are you expecting?

Create your form in design view.
Add a TextBox control.
Highlight it.
Select Events in the properties window.
Scroll to the Click event.
Double click it.
Add code to handle the click.

Or:
Add a handler to your textbox:

textBox1.Click += new EventHandler(textBox1_Click);

and provide the handler:

void textBox1_Click(object sender, EventArgs e)
    {
    throw new NotImplementedException();
    }

Then code your handler so it doesn't throw an exception...

Or was there something else?