If you're not a coder, I don't know how you're going to publish code... but I'll look past that.
The best thing to do is host the code on Github, then create a website for the project using Github Pages. At that point, gaining traction from the community so other people contribute to it has a lot to do with what the code is, and what it does. A good place to start is with solid documentation so anyone looking can quickly tell what your code does and whether contributing will interest them or be easy.
As the owner of the project, it will be up to you to allow or deny the changes that other contributors make to the repository. That is how Open Source projects are managed. I would suggest learning more about Git and maybe beginning to code a bit, so you can start to see what people are really changing in your codebase. Codeschool is a great place to start if you want online tutorials.
Best of luck!
One of the best platforms for open source is to put the project on GitHub... Tons of open source projects are hosted there. Another place to announce that you've opened source projects is to look at meetup lists. meetup.com is a great place and has a huge developer community. What language is your site built in?