@Phuket2 Latte is a system that allows you to install packages, and also has a command that generates templates for new packages if you want to create some. But it doesn't host packages itself. In fact, you can create your own Latte repository and host packages there with minimal setup. Just read my repository section at http://seanld.me/latte. Once you create a Latte repository, you can put packages in there (that you can create with latte new <package-name>, and people can add your repo by typing latte add-repo <url-to-repo> where the URL is the URL to your repository location (where the init.latte file is located).
There is no "main Latte repository". It's a decentralized repository system, meaning anyone can host their own Latte repositories with their own packages, and anyone can add those repositories to their Latte in StaSh and install packages from them. However, Latte does come pre-installed with my repository called universe which is directed at https://github.com/Seanld/latte-universe. You can copy what I've done at that GitHub repository and create your own, if you like.
It sounds complicated, it's not. Just check out the documentation on the aforementioned site. Once this thing catches on, I'm pretty sure quite a few StaSh users will start using it.