Where is my Seller Hub?!

I can never find my way around this site, once I find where some advice is,  ebay change the layout. I think I have a time waster buyer for my trailer, and would like to cancel their bid and go to the next highest bidder. They promised to message me this morning when they set out, but just as they should have arrived, 11:30  they messaged to say they may come tomorrow OR Monday.  Someone said yesterday,(I couldn't find my post) that I should not have given my address to the buyer before payment but ebay did not block it so I assumed it was normal. We have large gates on the drive so I felt it safe to give the address.