Easiest way to find any SSSI area is to use http://magic.defra.gov.uk/MagicMap.aspx which is Natural England/defras mapping portal. On left is 'Table of Contents'. Find 'designations' and click the + which brings up more options. Again expand 'land based designations' and then 'statutory' and scroll down for 'sites of special scientific interest England' (or wales/Scotland) and click the check box. A green overlay will show areas that are SSSI. The slidebar below 'designations' can be use to alter the transparency of this layer to allow base map details to be visible whilst still seeing the green shading of the sssi area.
You can you the 'Identify' button on the toolbar at the top to click on the sssi area (or any other feature highlighted in a data layer) to gain further details about the SSSI eg citation, views on management etc.
Takes some getting used to, but its a useful tool for some stuff.
Jim