I'm out of date on the image-generating side of AI, but I'd like to check things out. What's the best tool for image generation that's available on a website right now? Ie, not a model that I have to run locally.

There are toy AI things, but there is nothing quite like Stable Diffusion running on Colab. Lots of people recommended Midjourney but that is like playing with MSpaint. If you can get Stable Diffusion going with Automatic1111, its AAA tier. Especially with Control-net, and dreambooth, but that is part 2.

Google: The Last Ben Stable Diffusion Colab

for a way to not run it locally, but get all the features.

> The Last Ben Stable Diffusion Colab

https://github.com/TheLastBen/fast-stable-diffusion