101jinx101, these kind of images quickly amaze people, but it's not that difficult at all. It's all about using your eyes and some patience. That isn't too hard is it? Of course it helps a bit if you're good with Photoshop.
Even you can make what is shown here, you just have to believe in yourself. Trust me, it's not all that hard as you think.
Important is that you need to be interested to make that kind of stuff and you'll be amazed, serious.
101jinx101, if you want to make realism your ultimate goal, then you're better of with a 3D application.
Also, I've seen people trying to "show of" how good they are with Photoshop, just by showing a realistic object, but if you give give them a simple assignment as, "make a logo", "create an outdoor scene", "create a realistic water tap", "remove this color cast", "extract the hair", "hand paint a face", etc, then suddenly they suddenly come up with the most amateurish results. Don't be amazed that people who are good in one area, have a total lack of composition skills.
Just don't restrict yourself ok? 
