I tried to understand the SiteData / SharePoint web service format in Microsoft web site, and couldn't get a clear idea how it works. What I see is that the SiteData WSDL just returns strings (XSDANY), that you need then to decode using SharePoint schema. I have looked at several spécifications ([MS-SITEDATS], [MS-PRSTFR]), but impossible to understand where ows_LinkTitle and other attributes come from. It's a little bit too much abstract for me, and I'm not used for developing with Microsoft standards.
Anyway, I think you should first search for XSL on the Web (rather than ST).
Or do ST from scratch based on what you see/guess about what SharePoint web service returns (see Rüdiger answer :-) ).