Quastions about Placeholder Control

I have few question about place holder control,

I have one PlaceHolder Control. In my Place Holder i have 10 TextBox, I have one Button out of Place Holder, Place Holder is not visible, I have One Panel Control,

In my Button Click Event i have this code:

Panel1.Controls.Add(TextBox1);

this work fine but If I click twice then i want to add TextBox2 in panel , if  i click 3rd time i want to add TextBox3 in Panel , later if i click 10 times then

Panel should has 10 TextBox, i dont know how to do it , this is my first question.

My Next qustion is that , After adding First TextBox in Panel, when i add next TextBox, then  All TextBox should come with "<br/>" (break line) sooo that they will be arranged by theyselves one by one, let me know how i can do that form you all's answer,

If anyone of you know that ...