Apple, Google, Microsoft Avoid Taxes By Keeping Billions In Profits Offshore
huffingtonpost.com
huffingtonpost.com
As for "don't have to be this complicated", I completely agree. Where I live now, the government does your taxes for you, sends you the paperwork, which you can verify, fix if incorrect, sign, and send in.
I think this doesn't happen in the US because 1) companies make money with having loopholes, so they push for loopholes, 2) politicians fund their campaigns with said money, 3) tax preparation companies would lose money, so they would also be against this scheme, and 4) various people are morally opposed to both a well-run government and taxes, so would rather throw the baby out with the bathwater than work on an improved system.