Thank you for helping Tester.
Bradford, there isn't a single place where all templates are stored, since Oxwall works via Plugins.
/ow_static/themes/themename/ >>general.html, dndindex.html - are two general html pages used sidewide.
Html files for other pages are located, depending on the plugin they belong to.
Html files for system pages ( that are not part of any certain plugin) are located under ow_system_plugins/base/views/. For example join_index.html ( ow_system_plugins/base/views/controllers).
Html files for certain plugins are located under ow_plugins/pluginnamehere/views .