Hi all,
Thanks for your replies. I will do my best to respond to all...
1. I'm running OpenBSD 4.8 Generic
2. I installed Webalizer through package installation
3. Yes I've seen that page and many others.
I must appologize as I seem to have got mixed up with what software I am running. :P I wrote proftpd however I am running pure-ftpd.
I have since got this working by setting my pure-ftpd startup commands to force a partular log format. Both CLF and xferlog formats work fine.
This brings me to another question.
Without specifying a log format/path in the config for pure-ftpd it automatically outputs to /var/log/xferlog which I had figured was in xferlog format.
Clearly this is not the case. 
I notice that the info in /var/log/xferlog is actually quite detailed. Shows uploads/downloads and other info like when a file is deleted. Yet when I force xferlog in the config I only see when people access a file but not deletions..etc. I'm wondering if there is anyway to tell what type of log the "/var/log/xferlog" actually is?
A snippit of the log is below for reference (cleaned to remove usernames...etc)
Code:
Jul 1 00:15:49 myserver pure-ftpd[23519]: (?@1.1.1.1) [INFO] New connection from 1.1.1.1
Jul 1 00:15:50 myserver pure-ftpd[23519]: (?@1.1.1.1) [INFO] Logout.
Jul 1 00:32:29 myserver pure-ftpd[11500]: (?@1.1.1.1) [INFO] New connection from 1.1.1.1
Jul 1 00:32:30 myserver pure-ftpd[11500]: (?@1.1.1.1) [INFO] Logout.
Jul 1 00:49:09 myserver pure-ftpd[4163]: (?@1.1.1.1) [INFO] New connection from 1.1.1.1
Jul 1 00:49:10 myserver pure-ftpd[4163]: (?@1.1.1.1) [INFO] Logout.
Jul 1 01:00:01 myserver pure-ftpd[9548]: (?@1.1.1.1) [INFO] New connection from 1.1.1.1
Jul 1 01:00:06 myserver pure-ftpd[9548]: (?@1.1.1.1) [WARNING] Authentication failed for user [baduser]
Jul 1 01:00:06 myserver pure-ftpd[9548]: (?@1.1.1.1) [INFO] Logout.
Jul 1 01:05:49 myserver pure-ftpd[28242]: (?@1.1.1.1) [INFO] New connection from 1.1.1.1
Jul 1 01:05:50 myserver pure-ftpd[28242]: (?@1.1.1.1) [INFO] Logout.
Some other notices:
Jul 1 01:45:45 myserver pure-ftpd[29082]: (username@1.1.1.1) [NOTICE] File successfully renamed or moved: [New Folder]->[pictures12]
Jul 1 02:22:38 myserver pure-ftpd[9411]: (username@1.1.1.1) [NOTICE] Deleted /ftp/data1/bigfile.tar
Any thoughts would be great. Once again sorry for the mix-up!
Cheers!