how to put a left navagation bar in vB ?

Just put a left aligned table in your header.

which header ?

Header template.

do you mean header template under
options->change styles ?

besides this thread, is there any resource on the net that detail talking the structure of vb and which template to build up a page, what is the use of indivdual php files ?
I found the offical user manual is not very enough

Yes, or under edit templates. The styles is just an interface to certain templates.

And no, there's not an official template resource handbook yet, but I think someone detailed about 50% of them. There may be one for 2.0. And there's little need to edit any of the PHP files.

I added my test nav bar on the header template
but it appears at the top of the page as show below

http://free4home.dns2go.com/~adrian/screenshoot3.gif

cut: forumhome template
Copy: into a editer like Frontpage or dreamweaver.

Make a two column table and put all of forumhome in the right column and your links in the left column.

cut the code and paste back into that template.

I am going to make a book one day on this. :)