How Did Oz Know Where Angel Investigations Was?

[slayerpower]

Oz visits Angel in the first season, but how did he know where to find him? You could assume that Angel gave Giles his address in Buffy S4's Pangs, but that was before Oz visited him in In the Dark. Did Oz just going around asking if anyone knew where a goody-goody bumpy-headed guy was?

 

[Black Eye Guy]

It's not like the two groups completly cut eachother off, I'm guessing they still spoke and finding address's and such would be easy enough!

 

[white avenger]

He looked in the yellow pages.

 

[Angel's vision]

Saw the ads in Newspapers.....

 

[The Arcane]

I don't think this is that much of a mystery. As has been said, there is no reason why the two groups wouldn't have been in touch at that point. Cordy was back on speaking term with Xander again so it's very likely that once she was set up with Angel that she would have called to mention who she was working with. Sometimes you just have to fill in the blanks for yourself and assume the obvious.