Some Useful Resources:

General
eBusiness Law: A Practical Guide for Irish Companies
The Data Protection Commissioner                        
The Data Protection Act                                     
Guides to Privacy Laws  
 
Online PR
PR Web  has some good tutorials/explanations on online PR & also
This Boring Headline Is Written for Google” Article about writing news releases for search engines versus human editors:
 
Social Bookmarking  
Social Book Marking in Plain English
 
RSS
RSS in Plain English
 
Virtual Worlds
Second Life is experiencing a second life of its own. 

Twitter
Twitter – very basic tutorial
& also Twitter in Plain English
 
Widgets
A selection of ready made widgets
http://www.google.com/ig/directory
  
Inbound Links
To see inbound links, go to:
Yahoo Site Explorer
& then Insert the url of the site you want to see
Select ‘Inlinks’. Then,
Select  ‘except from this domain’ to exclude links from within your own site.
 
I hope these links to video tutorials, articles and guides prove helpful to you.