For those that are interested in this concept, Cal Newport wrote a fantastic book about this concept of developing a passion rather than "finding" it in his book "So Good They Can't Ignore You". Very highly recommend.
Also, it's currently on sale on Kindle (looks like $2.22 on the US store, $2.99 on the Australian store). I'm not sure what I think of the book yet, but people I respect have rated it highly.
First link tells me "this item is not available for purchase". From that page I search for the book's title and find the same thing (same product page, with same reviews, etc.) But with a 13.53$ price tag. Infuriating to realise that the price you get is based on who you are somehow.