Can someone point me towards a tutorial for installing either FreePBX, or a Webmin GUI for Asterisk 1.8.8 on Debian 6? Asterisk Thirdlane Multi Tenant PBX Manager and Asterisk Thirdlane PBX Manager are available for Webmin, but I can't find the installation packages and the second seems to be for CentOS. I would actually prefer a Webmin module and a standalone installation of FreePBX, or anything else is not an option. Any help would be greatly appreciated. I have Asterisk installed, but I'm having trouble with the GUI.
I'd recommend just getting the new FreePBX distro. If you are set on using FreePBX, it's the best, most stable, best supported way to go. Otherwise, there are tutorials on http://freepbx.org for installing it from source on debian:
There shouldn't be any reason why you couldn't have both webmin and FreePBX running at once, although I am not familiar enough with webmin to say whether there are any modules that will interface with FPBX. Below is a link to the download page for FreePBX Distro: