I have finished the Germany game I talked about. I managed a t237 victory. I did not create a single Great Work. I only built two pre-Industrial wonders (Oracle and Leaning Tower). I did not generate any tourism until t164.
I played a mostly straightforward science game up into the Modern Era, picking up Research Labs before Archaeology. I wanted to stay peaceful until later, but I did end up capturing a couple cities -- I played on the Great Plains template, which is very small and guarantees you'll have contested borders. I had an Honor-Babylon next door who DOW'ed me early, which meant I needed to build a bunch of Archer-types for defense. Once I had the units, I figured I might as well use them, and after racking up a bunch of promotions I was eventually able to clean up Babylon, securing my first plundered Great Works of the game at t164.
Things threatened to go a bit haywire when I discovered I didn't have oil. I improvised by researching Ballistics and upgrading a bunch of Machine Guns. Logistics Machine Guns tear through Industrial Era cities pretty easily, and I quickly secured the oil for Panzers. If 60-strength Machine Guns are good, 80-strength Panzers are even better. With 6 movement points, Panzers get around the map fast and are able to pillage constantly, so they never have to stop to heal.
I swept my way through the map, and ended the game with over 1,100 tourism. Victory after International Games was very quick. I believe my passive tourism generation was only about 10,000, but by wiping one of the culture leaders I was able to Musician-burn through the remaining Civs with ease.
One of the included images shows my Great Works collection. As I said, I didn't make any of my own. I did dig up around 8 artifacts. There are 31 Great Works visible in the picture, plus more off-screen (I have a lot of cities). This is more Great Works than you could possibly hope to make yourself, but why bother when you can just take them?