The Resource pack is not yet available through other means and is a heavy work in progress, and as such will only be available here for now. Any other releases have not been approved by me
If you wish to give it a test run feel free to download it and give your feedback!
Warning
To use the pack it must be extracted from the downloaded file the final folder structure should be resourcepacks \ Immersive-Interfaces \ assets + pack.mcmeta
Note
The required fonts are set in the English (United States) language, if you wish to use your own language you can execute the script created by @Wolphwood in assets/minecraft/lang/$_langs.bat