was just looking at your build and caught a couple things that might save you a little bit of money. If your going with a i3 CPU then the Z77 board is overkill. Z77 is really only necessary if you want to overclock. Id suggest looking at some H77 boards instead. In fact there is a H77 model of the exact board your looking at http://www.newegg.com/Product/Product.aspx?Item=N82E16813128567
. The other thing is that if your just going to be using integrated GPU from intel then the CX430 is also overkill. Thats a good choice if you ever plan on upgrading her with a dedicated GPU but otherwise id save my money and go for something more in the 300 watt range, in fact doing some quick calculations u shouldn't need more than 250 watts (I know its nice to have the extra power but if you know you wont ever need it then it will just make your system less efficient) . As far as cooling in those cases goes, really without a dedicated GPU you wont be putting off to much heat as long as your PSU is orientated properly in the case so it can help exhaust air from inside. Hope this helps some, I personally havnt done a SFF build but I've done a lot of research into them as that will be my next build.
P.S. Just noticed while i was looking around that silverstone makes the SG-05B
with a 300 watt PSU looks like it could be perfect for your needs