I have written an Eclpise plugin (an Error Parser for the CDT), and it works just fine in the debugger version of eclipse. However I cannot for the life of me figure out how to
Putting the plugin into the eclipse/plugins folder should work. If it doesn't, that usually means Eclipse has cached the plugins configuration for performance reasons. You can force Eclipse to rescan the plugins directory for changes by starting it with the -clean command-line argument.
The typical deployment mechanism for Eclipse is to use features. A feature includes plugins (in your case, probably just one), and can be installed through the Eclipse update manager. To deploy your plugin using a feature, you would do the following:
You should then be able to point the Eclipse update manager at the folder or URL containing the site.xml, and install your plugin that way. The advantage of this approach is you can upload the files to a website and deploy remotely.