Spring 2023: The Libraries' move to an updated version of Ex Libris's Primo catalog (we call it Search It here at WSU) seems to have messed up the ability to download a print book citation into Zotero using the book Item Type. Right now its saving them as Documents (ebooks continue to be properly saved as Books). You will need to change the Item Type from Document to Book and fix the bibliographic data as appropriate. Alternatively, and better, just use the ISBN using the "Add Item by Identifier" icon and it will add it correctly with more or less correct bibliographic data (although you'd still better check it to make sure everything is there correctly).
Note that if your item is something like a Congressional Hearing, Encyclopedia, etc., Zotero has always and continues to download them as the wrong item type requiring a manual Item Type change and some bibliographic elements editing. Dissertations do load correctly using the Thesis Item Type.
As of 7/2023:
Note that you may prefer to search in WSU WorldCat Discovery (either via Search It or directly). You can search just WSU's holdings, or "Libraries Worldwide:"
Just use the Zotero Connector as usual and it will download the citation as a Book. You may need to make some adjustments to the bibliographic fields.
Just use the Zotero Connector as usual and it will download the citation as a journal article. You may need to make some adjustments to the bibliographic fields. This method will not automatically download the article - you will have to do so from the fulltext options (if available).
These will download as Journal articles and will have to have the Item Type changed along with adjustments to the bibliographic fields.
Zotero does properly save a print book as a Book in WorldCat, however it is kinda weird. You will see a folder (which usually indicates more than one citation is available) instead of the usual Book icon. Just click it, select "Off-Campus Login" (I don't know why it does this) and it will be added to your Zotero Library as a Book.