There are many Frequently Asked Questions maintained on the HTCondor web page, at http://htcondor-wiki.cs.wisc.edu/index.cgi/wiki and on the configuration how-to and recipes page at https://htcondor-wiki.cs.wisc.edu/index.cgi/wiki?p=HowToAdminRecipes
Supported platforms are listed in section 1.5, on page 12. There is also platform-specific information at Chapter 8 on page 1624.