I'm not sure my full requirements came through in my original post so I will attempt to summarise them here.  Is this still achieveable with DNN?

* the ability to update and store attributes and opinions of wines in a SQL database
* the ability to allow users to subscribe so they can reference the book and get emailed or t really understand what DNN gives me and what I need to buy.  Any further introductory advice to get me started would be fantastic.

cheers,
Paul.

Yes, with DotNetNuke,

* you can use UserDefinedTable to create custom properties for each entries and define different views on this table, include a filter and a search box

* you can create a custom module for your individual wine database using custom properties and the option for users to add ratings and comments

* you can create a public role, registered users can subscribe to, for receiving a newsletter, e.g. on changes on the book or use a 3rd party newsletter subscription module

* you can create a secure folder, where documents can be stored, accessible only to users of security roles with granted access

* alternatively the content can be stored in Help module, like DotNetNuke Online Help, which can include images, flash or videos as you like