you cannot. The game was only available through Sega's online store when the the Netlink service was still up and supported by Sega. It is the rarest Sega Saturn game and when it does pop up typically sells for the $250-$500 range.
Nights Into Dreams--- - 1996 VG was released on: Japan: 5 July 1996 (Sega Saturn version) UK: September 1996 (Sega Saturn version) USA: September 1996 (Sega Saturn version)
Wing Arms - 1996 VG was released on: Finland: 1996 (Sega Saturn version) USA: January 1996 (Sega Saturn version)
Shining Wisdom - 1995 VG was released on: Japan: 21 July 1995 (Sega Saturn version) USA: June 1996 (Sega Saturn version)
Darius gaiden - 1996 VG was released on: USA: 1996 (Sega Saturn version) Japan: 15 December 1996 (Sega Saturn version) Japan: 20 December 1996 (Playstation version) USA: 1999 (PC version)
Sega Rally Championship - 1995 - VG was released on: USA: 28 December 1995 (Sega Saturn version) USA: 1995 (Arcade version) USA: 31 January 1997 (PC version) USA: 10 March 2003 (Gameboy Advance version) USA: 2004 (N-Gage version)
Sky target - 1995 VG was released on: Japan: 17 October 1995 Japan: 25 April 1997 (Sega Saturn version) USA: 1 June 1997 (Sega Saturn version) Japan: 14 August 1997 (PC version)
Fighters Megamix - 1996 VG was released on: Japan: 12 December 1996 (Saturn version) USA: 17 April 1997 (Sega Saturn version)
Fighting Vipers - 1996 VG was released on: Japan: 30 August 1996 (Saturn version) USA: 30 October 1996 (Sega Saturn version)
Panzer Dragoon - 1995 VG was released on: USA: 5 August 1995 (Sega Saturn version)
Daytona USA - 1994 VG is rated/received certificates of: USA:K-A
Daytona USA - 2001 VG is rated/received certificates of: USA:E
World Advanced Dai senryaku Kotetsu no ikusakaze - 1996 VG was released on: USA: 1996 (Sega Saturn version)