Have a question about how the TVTropes wiki works? No one knows this community better than the people in it, so ask away! Ask the Tropers is the page you come to when you have a question burning in your brain and the support pages didn't help.
It's not for everything, though. For a list of all the resources for your questions, click here. You can also go to this Directory thread
for ongoing cleanup projects.
It's not an exhaustive list, but there's Trope Epitaph and (for very problematic pages) Permanent Red Link Club
135 - 169 - 273 - 191 - 188 - 230 - 300
Tropes can be deleted for many reasons, and some of them do not preclude re-booting the trope name. (The new trope would need to go through TLP
just like any other new trope)
If you're looking for a list of Verboten tropes, you want to review the Administrivia.Permanent Red Link Club. These tropes and pages have been nuked down to bedrock, and then the cleanup teams have sown what was left with salt. They're never coming back - for good reason.
It's not a simple list and would thus require a lot more searching than what you're asking about, but the Repair Shop Morgue features past discussions from the Trope Repair Shop, including past cuts (I used it as a reference point for several Trope Epitaph entries), though the oldest threads were deleted back when the site purged old forum threads (that's not done anymore, so the oldest threads that are currently in the Morgue will stay there).
Is there a list of tropes that were removed?