As Aigo pointed out, we need more information and what your intent is. As a point of reference, if you look at some of the build guides on this forum and at OCN, you will see a reference list of items used in a build. This could help you formulate an idea of where you want to go.
Watercooling schemes can vary wildly, basic fitting if you don't mind tubing running all over the case, snake and 90 degree fittings if you want to clean it up and then what type of tubing, are you wanting to learn acrylic bending?
For instance, I build mine for silence and clean lines, so I probably have 20 fittings that aren't necessary (at $15 + each) just to meet my requirements. I always overbuild the rad space to allow me to run low-speed fans which is a trade off of slightly higher temps. Just sayin...