Beginner's Q: How to change the location of my keyrings?

[shang@skz.sony.co.jp]

Hello, this is Shang, a beginner to GNU PG and this list.

I know PGP has a environment variable "PGPPATH" which can
control the default location of the keyrings. How can I do this
in GPG?

And another question, Is there a search page for the archive of
this list? 

Thank you in advance.
Shang.