[NumLock]

еще один рабочий вариант (2 TListBox, 1 TEdit - все как у ТС):

Код:

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    ListBox1: TListBox;
    Edit1: TEdit;
    ListBox2: TListBox;
    procedure ListBox1KeyPress(Sender: TObject; var Key: Char);
    procedure Edit1KeyUp(Sender: TObject; var Key: Word;
      Shift: TShiftState);
    procedure Edit1Change(Sender: TObject);
    procedure ListBox2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

uses StrUtils;

{$R *.dfm}

procedure TForm1.ListBox1KeyPress(Sender: TObject; var Key: Char);
begin
  Edit1.Text:=Key;
  Edit1.Visible:=True;
  ListBox2.Visible:=True;
  Edit1.SetFocus;
  Edit1.SelStart:=-1;
end;

procedure TForm1.Edit1KeyUp(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
  if Key=VK_ESCAPE then
  begin
    Edit1.Hide;
    ListBox2.Hide;
    ListBox1.SetFocus;
  end;
end;

procedure TForm1.Edit1Change(Sender: TObject);
var
  i: Integer;
begin
  ListBox2.Clear;
  for i:=0 to ListBox1.Items.Count-1 do
  begin
    if AnsiStartsText(Edit1.Text, ListBox1.Items[i]) then
      ListBox2.Items.Add(ListBox1.Items[i]);
  end;
end;

procedure TForm1.ListBox2Click(Sender: TObject);
var
  i: Integer;
  Key: Word;
begin
  i:=ListBox1.Items.IndexOf(ListBox2.Items[ListBox2.ItemIndex]);
  if i<>-1 then
  begin
    ListBox1.ItemIndex:=i;
    Key:=VK_ESCAPE;
    Edit1KeyUp(Edit1, Key, []);
  end;
end;

end.

http://data.cod.ru/130546