The 2.0 version of XLS to XML for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The program is included in Productivity Tools. This free software for Mac OS X is an intellectual property of Dario Cruz.
From the developer:
XLS to XML is a portable cross-platform desktop application for file format translation between XLS/XLSX and XML. The tool allows you to configure the translation in a wide range of combinations to reach out your requirements. You can convert one or a bunch of files in a short time. No installation is required except Java. The simple and intuitive interface allows you to do complex operations with just a few clicks.
You may want to check out more Mac applications, such as DBF to XLS Converter, BeeCells XL or Air Hockey XL, which might be similar to XLS to XML.
Database Tools
Device Assistants