Multiple domains & where to search

[suy]

I have setup suse 9.3 following "The perfect setup for suse 9.3" from Falko.
Very nice!!! I only had to add zlib and zlib-develop.
I'm rather new to linux so...

Question: I also setup ISPCONFIG. After 4-5 reinstallations, it works...
1.I've put a website in the /web directory using an ftp program. But, I see there's also a user/web1_xxx/web directory? What's the purpose of it. How can I reach that???
2.During install I added also an additional ipadress (virtual). Why is it useful?

3. I want to setup more websites, on the same webserver. How? I tried to use "new site" in ispconfig, but I don't know where to look for the place (web) where I can put the php-files in (or html,...)

Thanks!!!!