Built-In Bunkbeds...any idea??

We just signed a contract to buy a house (yeah) so I can finally build the bed I always wanted for my girls room. I want to make them built-in bunk beds....i absouletly hate regular bunk beds (what they currently have) and would love to build them a system like this:

http://www.poetichome.com/wp-content/uploads/2011/04/built-in-bunk-beds…

I would probably rather have cupboard or drawer storage instead of desks...as we're homeschoolers and will have a homeschooling room with 3 separate desks for each of my kids and all that. Anyways, I have no idea how to even go about building a built-in bunk bed. Can you make plans Ana?? Or has anyone else done something similar?? I thought about having a contractor do it, but our area was flooded all last summer/fall and all contractors/builders are booked solid (besides of course being really expensive), plus i want to make it on my own! Can anyone help??

Thanks!
Julie