>>I have a trowel, handpick, and brush. What else do I need?

The trowel and the handpick (annoyingly) are the same tool basically. You'll need a bigger digging tool to start the excavation. I would suggest trying a larger general store like the one in Haven to find the tool you need to start.

Don't want to give too much away.. but you just need one more item to be able to start. With the tools you have you can help out, but can't start an excavation on your own.

Hope this helps some,
Grads

>>>Any chance we can see it somewhere like the Lost Crossing too?<<<

You'll likely see the excavation setup appear in quite a few other places, and the items you'll find will obviously vary by location. As to specifics, I don't know yet (aside from one, but I'm keeping my mouth shut on it).

Rigby