As subject says I am missing my developer cd. So I am happy to buy one if someone has one to sell.
Does one exist? I'm assuming so, but I haven't seen it dumped anywhere. 1.1's will install but there are some header conflicts.
All of the development tools for Mac OS X Server 1.x are bundled into WebObjects. Apple included a WebObjects 4.0.1 CD with all of their releases of Mac OS X Server 1.x, but from what I heard from my friends who did application development, you really should use WebObjects 4.5/4.5.1 with 1.2/1.2v3. That being said, any version of WebObjects between 4.0 and 4.5.1 should provide you with the full set of development tools for Mac OS X Server 1.x.
I've seen disk images for 4.0 around the web, but if you can find a WebObjects 4.x box set it comes with a lot of nice manuals.
A nice additional resource would be the Rhapsody Developer's Guide by Jesse Feiler (from 1997), but you can also find good info from Cocoa developer books from the early 2000's (when the developer tools for Mac OS X still resembled those of Rhapsody/Mac OS X Server 1.x).
Hope that helps a little.