Here are a few tips I can share from my recent experience installing bugzilla on centos. I won't say this is the best way or the only way, or that it will work with your centos (or god forbid non-centos), but it did work for me, and this roadmap might help you a little.

1. Download Bugzilla, extract, and run the included setup utility: "./checksetup.pl" (I downloaded and installed as one of my standard users who owns the "/bugs" directory in /var/www/html that I created for this purpose.)
2. For me, I had a variety of missing required and optional perl modules.
3. So as root I did:
   • yum install perl-TimeDate-1.16-1.el5.centos.noarch
   • yum install perl-Email-Send-2.183-1.el5.rf.noarch
   • yum install perl-Chart-2.4.1-1.el5.rf.noarch
   • yum install perl-Template-GD-2.66-1.el5.rf.noarch
   • yum install perl-GD-Graph-1.43-1.2.el5.rf.noarch
   • yum install perl-Email-MIME-Modifier-1.442-1.el5.rf.noarch
   • yum install  perl-Template-Toolkit-2.20-1.el5.rf.i386
   • yum upgrade
   • yum update
4. Unfortunately, Perl's CGI module is included with the main perl module, and even after I had upgraded and updated, the CGI that was installed was 3.12.  Bugzilla will not install without a more recent version.  After searching and fighting, here is how I ultimately installed the most recent perl CGI module (as root, in /root/localrpm):
   • yum install perl-FCGI-0.67-1.2.el5.rf.i386
   • wget http://dl.atrpms.net/all/perl-CGI-3.42-8.el5.noarch.rpm
   • wget ftp://distro.ibiblio.org/pub/linux/distributions/smeserver/releases/7.4/...
   • rpm -i atrpms-73.1-1.noarch.rpm
   • rpm -i perl-CGI-3.42-8.el5.noarch.rpm
5. Now back to the user who owns the website directory where I had unpacked bugzilla, and I'm happy to say that the installer accepted my configuration.
6. created the mysql database
   • mysql -uroot -p
   • create database bugs
   • grant all privileges on bugs.* to 'bugsuser'@'localhost' identified by 'password';
7. modified the bugzilla configuration file "localconfig" appropriately
8. ran "./checksetup.pl" yet again - and installation appears to have been successful.
9. I also had to run "chmod -R a+r ." and "chmod -R a+x ." - I'm not sure why the tar opened up as if my UMASK had been set too high, but anyhow this fixed the final issue ("Can't locate Bugzilla/WebService/Constants.pm in @INC ...)
10. One last issue - "chmod 777 data"