Call Conference Web Sign Up

I recently deployed some Trixbox PBX and hosted it a colo.I have completed all setup and all features that I need for my business are working fine.

Now I have a website hosted with a separate provider and am looking for pointers on how I could use my website as front end for users to sign up for call conferencing hosted on my Trixbox.

Right now I do international call conferencing but my customers have to email me to setup the conf bridge and then they SMS their conf participants with the login credentials.

I want to automate this.