Download of Theme Designs for iWeb 3.0 for Mac was on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The actual developer of this software for Mac is UAB Macmanus. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe. The software lies within Productivity Tools, more precisely Office Tools.
From the developer:
Theme Designs for iWeb are ready-made web design solutions, which can be used as a basis for fast loading, easy to build and high-quality website. To build a website using our iWeb Templates will not last long and all that time will pass with fun and in an excellent mood. Theme Designs for iWeb app contains 20 different designs for your amazing websites and you just need a Mac with Apple’s iWeb from iLife ’09 or later to use it.
You may want to check out more Mac applications, such as iWeb Theme Designs, Themes Box for iWeb or TurboCAD Mac Designer, which might be similar to Theme Designs for iWeb.