Data Miner
You end your search on the Mayan Cutter, and start the search for information on Rebecca MacCallister. This one takes a little bit longer, but not too much (in the neighborhood of 10 minutes, but that's for the search and sifting through all the junk that comes back with the actual data).
Based on what you can find, Rebecca was a student at UWash, studying up on the Ork Underground. She was writing a paper on its history and importance to the city of Seattle, and you find a few articles by pure happenstance through cross-referencing about the OU not being a formalized part of the city, and that it is one of the few areas that both KE and Lone Star help provide policing for (although you know that the policing isn't that much).
A couple of articles you find make reference to the fact that she was a mage, and that her father used to be a shadowrunner. There also seems to be some information that connects her to the Skraacha, and that rumors have it she was involved heavily with one of their leaders.
Artair, Oppenheimer, and Father Twilight
Finding the entrance to the Ork Underground is easier than placing an order for a soykaf here. The Big Rhino has 1 of the 2 public entrances into the OU, and it also happens to be a stop on the OU tours that take place from time to time. And at the thought of wageslaves and vacationers paying money to go underground, you almost chuckle to yourself.
The entrance itself is in the back of the restaurant, near the kitchen, and it's easily found thanks to the signs pointing to it. The staircase is well lit, until you get about half-way down, at which point no more than half the lights are functioning, and some of them are blinking and on the verge of going out. There is a stand at the top of the stairs that has the usual tourist map on it, but Rebecca lived in one of the residential areas, and because of the make-up of the OU, you aren't sure which residential area on the map it is. Heck - due to what the OU is, you aren't even sure the correct residential area is even on the map.
The OU itself is a unique experience, with part of it being old downtown Seattle, with other parts of it being roughly carved stone and dirt tunnels no wider than a single person could fit through. As you hit the bottom of the stairs, you can see the residents and nearby shop owners giving you that look. You know the one - the look that asks what you are doing down here, seeing as you don't live here. You can tell that they aren't mean by any stretch at this point, merely annoyed that what appears to be yet another group of runners or tourists is coming down to screw up their day.
Solifuge
Almost as soon as the others head towards the entrance to the OU, one of the largest trolls you've ever seen walks through the front door of the Rhino. Even if you didn't know who it was, it wouldn't be hard to place him thanks to the badge swinging on a chain around his neck and the large Ruger Super Warhawk on his side.
Tosh sees you sitting at the table and walks over, shaking your hand when he gets there. He sits down, and even though the chairs are built for Orks and Trolls, it groans under even his heavier than normal weight.
"Good to see you, Sol. Sorry about throwing your name to Mac, but he needs help and I thought this would be up your alley. I'm sure you've got questions for me on the case, so as long as you're attending the policeman's ball - I got a few tickets here..."
He puts his hand inside his jacket and pulls out 4 tickets, and from the print on the front of them you can see they are valued at 100 nuyen each.