If you think that German voting laws are complicated, take a look at the American System.
American voters have to register before voting, are invited to lengthy primaries and in the end don’t even get to vote directly for their President.
After this Podcast, the German “overhang seats” (Überhangmandate) will seem a rather trivial issue.
US presidential election
All the details about voting in the States at Wikipedia
Register to Vote!
Register to vote for the next presidential election, or just find out what qualifications you have to fulfill (besides being citizen of the US).