I'm trying to updgrade from EE1.7.1 to EE2.9.2 by following the steps outlined in the documentation here https://ellislab.com/expressionengine/user-guide/installation/upgrade_from_1.x.html
The process seems straightforward enough, and I have run through it as a test and it seemed to work (except for addons). To my mind the biggest problem that I have is that I have no idea how to tackle this note right at the top of the upgrade page.
Third-party add-ons from version 1.x will not work with ExpressionEngine 2. Please contact each add-on’s author for a 2.x-compatible version before upgrading, or your site may not function properly. The installer will automatically disable all extensions as part of the upgrade process.
How do I work out exactly what addons I have and who the author of each addon is? And what happens if there isn't a 2.x compatible version available?
Has anyone put together a more detailed how to guide on the upgrade process somewhere?