Problem fixing shelves to plasterboard

[skinio]

I want to fix some floating shelves similar to these [/url]http://cgi.ebay.co.uk/3-x-IKEA-BEECH-EFFECT-FLOATING-SHELVES-/120619280089?pt=UK_Shelving&hash=item1c157826d9 to a plasterboard wall. Could somebody please reccomend the type of fixings which are best to use. I have been looking at redidrive anchors.
thanks