When not dealing with ipsec on Cisco routers and Cisco firewalls I like using OpenBSD. Here is a good example for the latter 
http://stuffresearch.tor.hu/?p=64

The biggest problem I had with learning about ipsec was getting to understand all of the terminology and the composite parts and that usually isakmp is used as well though there are alternatives to isakmp.

I don't have a specific set of resources I recommend though as I  have not really looked at what's out there nowadays. I just know most of what I need at this point and only do a quick google for specific details as necessary. 



-------- Original message --------
From: Brian Wood <woodbrian77 at gmail.com> 
Date:  
To: tclug-list <tclug-list at mn-linux.org> 
Subject: [tclug-list] IPSec plans 
 
I'm going to take another crack at IPSec and would like 
to ask for advice as far as books, websites and tips 
related to IPSec.   Thanks.

Brian
Ebenezer Enterprises
http://webEbenezer.net
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