There was a download of LT Architect 5.0 on the developer's website when we last checked. We cannot confirm if there is a free download of this software available. We recommend checking the downloaded files with any free antivirus. This program is an intellectual property of CADlogic Limited. The software belongs to Photo & Graphics Tools.
From the developer:
LT Architect enhances AutoCAD LT by providing tools for adding architectural details to your drawings and functionality to automate much of the building design process.
You may want to check out more software, such as Chief Architect Premier X7 64 bit, AutoCAD LT 2013 Service Pack 1.1 or AutoCAD LT 2015 Language Pack - English, which might be similar to LT Architect.