Your best bet is to make one yourself. We did this in college to conserve space. Get the dimensions and borrow the design from furniture on display. A saw, drill and hardware (nuts, bolts, washers) is all you really need. Have someone who is handy with tools assist you. If you want to get fancy you can paint the wood or seal it. Don't go cheap on the support legs - 4x4 lumber is not cheap but it will keep you from crashing down - or use two 2x4 coupled together. Shalom.

I like SteelerzGuy2011's answer, but if you do not feel up to the task of making it yourself you can just google "Full Loft Bed." There are quite a few companies who make these... Ikea is probably the easiest one to buy from because you can pick it up immediately (and you won't have to pay for shipping).

I was wondering where to buy a one person bunk bed for a full sized mattress and have space underneath the bed for a desk and stuff on trusted sites such as target, meijer, etc. Thanks (: