Page not found Error on Fresh Install

I’m new to RT and I was trying to install it for the first time. I followed the guide located at this link http://wiki.bestpractical.com/view/DebianLennyInstallGuide and for the most part had not problems. The only problems I had were that apache wouldn’t start with this line Set(@Plugins,qw(RT::FM)); in the RT_SiteConfig.pm
file and I am unable to run newaliases. I receive this error: newaliases: fatal: open /etc/postfix/main.cf: No such file or directory. Then when I go the the web interface for RT it looks like the .css file is not loading and none of the links work. All of them say “Page not found”.

Here are the details of the versions I am running:
Linux svrrt 2.6.26-1-686 #1 SMP Sat Jan 10 18:29:31 UTC 2009 i686 GNU/Linux
RT: our $VERSION = ‘3.8.2’;
This is perl, v5.10.0 built for i486-linux-gnu-thread-multi
!DBIx::!SearchBuilder: 1.54
Apache: v2
mysql Ver 14.12 Distrib 5.0.51a, for debian-linux-gnu (i486) using readline 5.2

Any help would be appreciated.