for the mainboard try to get one with chipset z77 so that if you upgrade to 3570k you'll be able to use all the features and from my point of it's worth it. and they are fairly cheap for example
http://www.asus.com/Motherboards/Int...t_1155/P8Z77V/ the asus p8z77 I found it for 111.96Euro and it has the most important features for it's price (i live in EU too GR).
Also for the RAM 1600CL9 2x4Gb is perfect. the timings are much more important than the actual frequency so anything around cl9 would be the sweat spot.Generarly what I look for on a RAM is:
1. 1600mhz (at this point I dont know in 2-3 year's time what will happen)
2. Cl9-Cl8
3.low prof (if you are gonna overclock at somepoint and thus you are gonna need to add an aftermarket cpu cooler it will probably not fit if you have ram's with enormus heatsinks)
4. 1.5 volt approx. (higher voltage models are hard to find now, except 1.65v, but i believe this is the sweat spot because it's energy bill-friendly :P)
5. (unless you are gonna do heavy multitasking) 2x4gb is what you want
for the hard disk i would go for an ssd if possible because the speed is "OMG WTF OH YEAAAAH" compared to a conventional hdd :P (for the most part that is there may be exceptions but i havent found one so far)
the case is mostly a matter of preference, just look for one that is kinda spacious and that it's good quality. Cabble management and number of fans for airflow is what you should look for in a case according to your budget
for the PSU try to find one that is at least 80+bronze for efficiency and look for the Over Voltage/Under Voltage/ Over Current / Shortcircuit protections
As for the cpu I think that the 3570k is worth the extra money. I am too getting one and I am so far more than happy with the reviews. plus you can overclock it to 3,8-4,1 Ghz with the stock cooler (provided you have a z77 mobo)