I found Crucial were the cheapest when I upgraded my Mac to 4GB, always worth a try.
Always found them very good. Hassle free returns/warranty too. Go direct to their website.scan.co.uk? corsairs XMS is pretty reasonable price at the moment..
i got my last lot of memory (geil black dragon 2x 4gb) from an ebay retailer as it was cheaper..
edit - oh you want 1066, not sure they do the XMS in that.
edit 2 - yes they do.. how much do you want?
overclockers is free delivery if you are a regular member of the forums.
www.scan.co.uk
www.novatech.co.uk
www.misco.co.uk
www.dabs.com
http://www.novatech.co.uk/novatech/dirresults.html?s=1066 ddr2
I couldnt find an option cheaper than £7![]()