My friends and I want to host a private SMP for Minecraft 1.0.0 as we wanted to beat the game with old standards. I dont seem to find the .jar file or .exe file for the server. Some people said It was on the 1.0.0 wiki, but there wasn't a downloadable file to be found. Are there any archive sites where I could find it? I've went to mcversions.net or mctimemachine.com but none of them work at all. Hopefully there's an archive where I could download em
Yes. As you mentioned, you can download the Minecraft 1.0.0's server's jar file (and .exe file) from fandom, it is found at Java Edition 1.0.0 page, screenshot below.
Click your Right Mouse Button and select
Save link as... (or whatever it's called on your browser) and select a location to save, and the file will be downloaded at the selected location.