Ah yes. I know those. I call them "Scrap iron" and put them in the trash can.
In all seriousness, the second picture looks strikingly like a rusted crescent wrench... even down to the hole on the bottom. Oh wait..> just re-read your post. You already identified that one. DANG. And here I thought I was awesome. Ah well.
Someone more familiar with Relics might be able to help you out on the others.
Hang in there on the AT Pro. I love mine, but the first few weeks of learning curve were hurtful.
Oh, and if you' don't have an actual pinpointer, you might consider one. I use the "wiggle" method to find the target (wiggle back and forth over the target and back up until it stops, the target is under the top end of the coil). Saves time trying to "pin point" using the button. The DD coil is excellent at this. Once you've got the location vertically in the ground, it's just a matter of testing if the pinpointer can pick it up, and if you have a variable pointer (like the Garrett Pro Pointer AT), you can tell how deep the target is. If no beep, dig a deep plug. if a medium beep, dig a medium plug, if a rapid beep, dig a shallow plug, if a tone, pry it from the surface!
Cheers,
Skippy