I know it says "compatible with all raspberry pi models" but is it actually compatible with the RPi zero and RPi zero w? I can't find anything about DSI ports for them.
It is not compatible. The Pi Zero (all models so far) lacks the required connector.
According to Element 14, the display is compatible with:
- Raspberry Pi 3 Model B
- Raspberry Pi 2 Model B
- Raspberry Pi Model B+
- Raspberry Pi Model A+
The display will technically work with the Model A and Model B boards (connecting it to the DSI port on the Pi board), however the mounting holes on the back of the display will only line up with the newer board design (A+, B+, Pi 2 and Pi 3).
In other words you'll have to do a bit of fiddling to mount it on the A and B models and won't be able make use of the built-in stand-offs, but it will work.
(Note that what almost nobody tells you except in the smallest print is that the official 7" touchscreen has rectangular pixels. This squashes images, and can look very unpleasant. You might consider its non-compatibility as a lucky escape, on that basis.)