Little update, I needed a couple of 12's recently for a project and found the listing below has a pretty good selection for 12v and 24v switching power supplies: 25W/30W/50W/60W/100W/120W/150W/180W/250W/300W/360W/400W

12v 80w 6a £10
http://www.ebay.co.uk/itm/282219610030

12v 25w 2a £6.50
http://www.ebay.co.uk/itm/282219610030