CategoryService extending/over-ride plugin

Hi,

I want to produce a plugin to override/extend the CategoryService, can anyone provide any help with this?
such as is it possible, and how I would go about doing this?

I am fairly new to writing plugins, I've written plugins for other systems, but I am struggling here as there doesnt seem to be any examples for me to look at, which do anything similar to what I need to achieve.

I know I can achieve what I want by directly editing the CategoryService, but I want it in a plugin to try and avoid issues when updating.

Many thanks for you help on this.

nopCommerce Version: 2.30

I think I've found how to do it here: http://blog.csharpwebdeveloper.com/2011/09/23/nopcommerce-plugin-with-data-access/

Just need to work out how I get the current login customer now :)

JamesStuddart wrote:

Hi

For example  _workContext.CurrentCustomer.Id will give you the ID and  _workContext.CurrentCustomer.Email the email :-)

Ah! that looks nice, Im using httpcontext atm.

Once I have this plugin working ill change it ;)