If you meant "the hot keys available in cadence plots" (whatever that means), then why did you explicitly ask for Schematic and Layout?
If you're talking about the ADE or ViVA graph window, then it will depend upon which version you're using - and you didn't mention that. If it's IC615 or IC616, then the bindkeys are in the same place (the Options->BindKey form). If you're using IC614 or before, you can see them in the pull-down menus in the graph window next to the action, and you can also see some in Help->Shortcut Keys. Also, if custom keys have been loaded, they'll show up in the the Options->BindKeys under "wavescan").
There's no link on the web site showing them - because they're customizable, and so may be different for different customers or even different users, depending on what they've chosen.
For your second question, go to Community (just click on the link at the top) or Community->All Forums. You'll see your name on the right side, with Edit My Profile, View Profile etc. Just click on your name, and then there's an option to "Search for posts by Andrew Beckett" (that's what I see) - this will be sorted by date from most recent first. If you use Community->All Forums you can click on Forum Subscriptions and see which forums you're subscribed to.