You may find weescotts' article helpful and with links
http://forums.overclockers.co.uk/showthread.php?t=17598033
The thread will give you an insight.
For quad core cooling i would highly recommend a D-Tek Fuzion cpu bloc .
http://www.thetechrepository.com/showthread.php?t=85.
D-Tek Fuzion flows significantly better than any other CPU block giving it a distinct advantage in multi-block loop performance
http://www.xtremesystems.org/forums/showthread.php?t=131297
The D-Tek Fuzsion nozzle accelerator kit has just become available as well for this block, included is the quad core core nozzle accelerator
Swifttech vs D-Tek Fuzion
http://www.xtremesystems.org/forums/showpost.php?p=1949570&postcount=84
Clear Acrylic blocks i avoid as they are prone to cracking around the barb area.
The radiator most probably recommended by forum members would be probably a ThermoChill PA120.3
http://www.overclockers.co.uk/showproduct.php?prodid=WC-002-TO&groupid=701&catid=57&subcat=193.
Rads with less dense cores such as the Thermochill PA series get away with lower speed / quieter fans For example yate loon. The shroud to accompany this radiator i would also recommend as it eliminates fan dead spots over the rad.
As for hose size/ barbs would be a personal preference either 3/8, or 1/2. There is no difference regarding performance between the two.
As for the pump you could consider a Laing DDC 12v pro water tank (volume 110ml). The res is attached to the pump (110ml). Space saving and removes the need to place a res in a bay or o/s the case.
Regarding tubing i would use Tygon as it is laboratory grade tubing. It is flexible, clear and also kink resistant. Due to its laboratory grade film deposits do not build up and line the inside of the tubing.
Other members will, im sure have further input.
As to your gtx you could either use, EK, Fuzion, Danger Den ect. I personally use the Danger Den as it is a full cover block and allows the use of the PCI slots on both sides of the card.
http://www.overclockers.co.uk/showproduct.php?prodid=WC-004-DD&groupid=701&catid=57&subcat=193.
You will find the links in weescotts' guide helpfull with the graphic card blocks helpful as well.
As to fluid i use Feser1 all though there are others on the the market.