How can you determine an IP address?

Per the following instructions...

"In access hosts you need to put the IP in not the domains, you should
allow access to both the server IP of mysite.org and also the IP it is
hosted on (if different to the server IP.)"

I need to know my webhost's IP address so I can make a remote database
connection. But I can't find his IP address in my notes, and I haven't
been able to get a hold of him this weekend, probably because of the
holiday.

I know my website's IP address, but is there a way to determine the
other IP address, the server IP?

Also, how would I log both IP addresses in under Access Host? Do I put
them on the same line, separated by a comma, or do I enter each one
separately, in two different operations? Should I put a % at the end of
each IP address? I noticed that it doesn't seem to register unless I add
the %.

Thanks.