I don't have a bunch of time to make a long drawn out article like I did for gaming CPUs but I did want to mention a few things.
If you have a stock cooler, please do not overclock your CPU. You are taking a risk at damaging your components because the heatsink isn't big enough to dissipate heat fast enough. They barely meet TDP as it is.
If you have no intentions of benchmarking and you have a modern CPU, you don't need to OC. Simple as that. It's fun when you know how, but that 2500k is fast enough stock and OCing for the sake of OCing and nothing to get is simply generating heat for nothing.
That aside, we have had a lot of requests here about water solutions.
My first answer is going to be this. If you have NO experience overclocking, and have NO experience with coolers then head on over to Google
and search for guides. Do your research first, then play with your toy later having the confidence of knowledge in your hands. Please, I don't want to see in troubleshooting your dead CPU or board because something went wrong. We are here to help and answer any questions, but the first place you should go to is Google for guides that are already there.
My second answer is gong to be, no I don't recommend that huge pile of metal over an AIO. If you don't know what AIO means, it stands for All In One. Pointing towards units such as the Corsair H50 ect. To continue on that, I recommend the H80 and H100 to anybody who will not be going for extreme 24/7 OCs. If you want to get that 3570k to 4.5 then an H80 in push/pull setup will do the trick, and the H100 even better. Do you need a 4.5GHz 3570k? No, not really.
Third answer, so you have a little play money and are either being foolish or have done your research and want to get your hands into custom water. Well, lucky for you the market is all about laziness and simplicity. A few companies such as EK and XSPC make kits that come with everything you need. Just set it up. One such kit is this:
EK-KIT H3O 240 LTX - Kits - Kits & Watercooling Cases
These kits such as the EK I linked aren't full of their top notch hardware, but for the money what you are getting is a cheap complete kit that will outperform any other typical cooling solution you can find on the market. If you are going for silence then you can grab a GPU block and on stock clocks a 120.2 fat rad (such as in the kit) will cool both nicely and you can mount some quiet Noctua fans on there. If you are going for overclocking I do not suggest that, but rather a 120.3 (or 360) rad. TDP and heat output for modern CPU and GPUs have dropped within the past 2-3 years meaning you don't need a dual loop system unless you have SLI or more.
If you want to make a completely custom kit there are a few here such as myself who would be glad to assist you in compiling all of the parts you need to do such a thing. Earlier it sounded as if I was warding away from custom water, but really I'm just saying it isn't necessary to waste the money if you don't have to.
Happy OCing, and don't forget to post your benchmarks and pics.