If you are set on the Q11, check New Lian Li PC- Q11 itx case : Specification & Feature
, you can see a lot of builds and combos there,CPU Intel i5 2500
, its good quad, but check if you really need that much cpu power, else an i3 might be enough..CPU heatsink?
= In the thread above you will see some builds using the Thermalright AXP-140
, i believe the 140x25mm fan wont fit with a standard psu inside, but there is one using a slim slipstream, the good thing about it is that it will not block the pci slot of most of the mini itx board, while still being relatively low profile cooler. Other are using Big Shuriken, but i might block the PCIe slot, check the thread for what coolers they have used.Motherboard?
= Here you have a lot of choices, since you are not OCing, go with H67 mobo, get one with the features you want.PSU ~500W?
= Seasonic SS-560KM
or KINGWIN LZP-5502x4GB RAM?
= Here go with ram that has been used already with the mobo you end up choosing, personally i like gskill eco, ripjaw and snippers, check the CPU heatsink you end up buying, for the AXP 140 is like 40mm, so check the ram doesn't exceed this height.SSD HD?
= Crucial M4 CT128M4SSD2 2.5" 128GB
, a proven ssd, good price and performance. GPU GTX560?
= Gainward GeForce® GTX 560 Ti 2048MB "Phantom"
or Gainward GeForce® GTX 560 1024MB "Phantom"
, are well regarded (personally i havent tested it), but its not available everywhere.