I am just trying to update to 2.3, and at the same time I am updating some plugins (that notification functionality is neat!). So one of them needed to be patched to work in the slightly non-standard setup I have. To do this smartly, I needed to find out how I can get the plugin path.
After about half an hour trying to find what I need in the Codex, I gave up and just hardcoded it in an extremely ugly way.
Let me be frank: The wordpress documentation is a complete mess. It's outdated, it's badly organized, it seems incomplete, and above all, the search engine sucks.
Please clean up that mess, so that people who are not hardcore wordpress developers stand a chance to figure out how to do anything. Your benefit: You'll have a much greater chance for someone like me to actually contribute something worth-while back. Had I been able to patch the plugin in a good, universal way, I'd be able to submit it back to the maintainer, and other might benefit.