The Atari 7800 ProSystem was released to the general public in June 1986. Fixing many of the shortcomings of the Atari 5200; including being backward compatible with 2600 games. Although the 7800 sold well it had a hard time competing with Nintendo's 8bit gaming system which was dominating the American market at the time.
Are you looking for Atari 7800 Games? Or perhaps Atari 7800 Controllers?
Atari 7800 notes:
-Only about 60 games were released on the Atari 7800.
-The sound quality on the 7800 is virtually the same as the 2600.
-The advertising budget for the 7800 was extremely low compared to what was being spent on Nintendo and Sega systems.