[cyborgg4655]

Попробуй так:

Код:

procedure TForm1.Button1Click(Sender: TObject);
var
Doc: IHTMLDocument2;
  Buttons: IHTMLElementCollection;
  Button: IHTMLElement;
  i: Integer;
begin
  Doc := WebBrowser1.Document as IHTMLDocument2;
  Buttons := Doc.all.tags('INPUT') as IHTMLElementCollection;
  for i := 0 to Inputs.length - 1 do
  begin
    Button := Inputs.item(i, EmptyParam) as IHTMLElement;
    if AnsiSameText(Trim(Input.innerText), 'Текст кнопки') then
    begin
      Input.click;
      Break;
    end;
  end;
end;