Not sure how to search, but here are the games from the Gambit Gang Internal King's Gambit tournament and Muzio Gambit thematic.
How do we search a specific master's games for a specific opening?
Here's Gonnosuke's KG games: http://www.chess.com/games/results.html?f=4&t=2&pid=45095&white=1
If you want to do that for a specific player go to their profile -> Explore games, pick the side you want, then play the moves out, and then you can click to view all games from current position (note, premium membership required past move one).

Thank you very much. I can get there from the link. However, could you teach me how to fish - how to search myself in the future? Sorry to be stupid, but from Game Explorer menu, I don't see how to go to a specific person's profile. If you click on "chess games and openings" link, that page has 4 different boxes, but doesn't tell you what each box is for??? I put Gonnosuke in a couple, but got no results.
Thanks for your help
When you're in the game explorer, go to the drop-down menu where the default choice is 'Master Games.' Change this to 'Other Players Games' and then type the username into the box to the right. Alternatively, you can go to their member profile and use the 'Explore Games' tool.

Thank you. When it said to put in a user name, I just assumed that was for other site users - not master's games.
I am specifically looking for Gonosuke's games playing the King's Gambit, but was unable to get any games coming up in search area.