Quite some while ago, I played a bit of this game on Steam. It was the base game--no DLC, no expansion pack, and with few if any patches out.

I seem to remember there being a "zombie journal" of sorts in game. It showed a picture of a zombie type, along with its name, some text, and some stat bars.

I'm now playing the GOG version that includes the expansion + some of the DLC, but am not finding that zombie journal. It is bugging me because I'm pretty certain it was there before :/

Does anyone know how to get to this feature? Was it patched out? Am I imagining it?

I haven't been playing the game all that long yet either, but I haven't seen this feature.

The closest thing I have seen is the "tack board" by your sleeping bag/duffel bag in the upper levels of the Tower. As you face new zombie types there will be photos tacked to the board of the new type with its name. No stats or real description from what I have seen though, and if you just always camp out in the lower level of the Tower I don't think you would ever see it.