Hello! I'm interested in building some DIY ASCI USB miner just for fun/learning purposes. I bought some Antminer U2 recently and got interested to know how it works from the inside. I found one thread here
https://bitcointalk.org/index.php?topic=161715.0
but it seems to be a bit old.

Could you please point me at some references, where I could start? I'm particularly interested in knowing where you can source parts (like ASIC chips).
Any information would be greatly appreciated!
Thanks in advance!