In reply to Fraser:
Here you go, from this link:
http://www.ukclimbing.com/forums/t.php?t=411034&v=1#x5868284:
This list (in no particular order) may be of some help - it was when I was selecting holds for my woodie. Not all the manufacturers are in the UK and not all are 'interesting', but it's a maybe starter for you:
www.coreclimbing.co.uk/home/Core-Climbing-home-c-276.html
www.planetholds.co.uk/cat-Collections-14.aspx
www.slvtr.nl/index.php?j_node=10
www.customholds.com/climbing_holds.htm
www.rockworksclimbing.co.uk/
www.rockcandyholds.com/
www.slapholds.com/default4.asp
www.lapisholds.com/
www.elementclimbing.com/
www.soillholds.com/cart.php?m=product_list&c=79
www.voodooholds.com/servlet/StoreFront
www.revolutionclimbing.3dcartstores.com/
www.synrockholds.com/holds.html
www.climbingholds.com/index.php?target=exceptions&exception=no_page
www.holdz.co.uk/
www.hrt-holds.com/
www.expression-holds.com/english/holds.htm
www.ep-uk.com/store/browse/1
www.climbholdfast.co.uk/bolt-on-holds.htm#accessories
www.beaconclimbing.com/bolt_on_holds.php
www.threeballclimbing.com/rockclimbingholds/bouldering1.htm
www.summithut.com/products/wood-grips-5-pack/
www.moonclimbing.com/hardgoods/bolt-on-holds-c-302_318.html
www.metoliusclimbing.com/bulk_bolt-on_holds.html
F