I'm pleased to report that on three or four consecutive days, everything I looked for has been in the expected place. A paper-cutter, rarely used, sat meekly in the craft box in the cupboard. An Irish grammar book - the corner of the guest room, in a stack of similiar Irish-themed books. All bathroom items very easy to locate in their drawers and cupboards.
The two mail-ready letters I am missing turned up at the bottom of my handbag. I found them at Mass when I was looking for the collection envelope. However, I'm indulgent with myself about these - I was jetlagged when I put them there. Less forgivable however, is that I didn't look for them properly in my bag. They had sunk to the bottom. I often think the interior of my handbag has a force of gravity greater than found anywhere outside.