The idea of an aquascape is essentially an underwater garden that releases oxygen into the room. You can make them into mini-biospheres (ala Make 10), but this one won't require you to pick things out of a pond.
Step 1: Aquire the Materials
You will need a container (glass jar, bottle, cup) about $6 for mine
Gravel (Ikea has small bags for $2, enough to make two of these)
Plant bulbs (I picked these up at Wal-Mart(BOO, HISS) for about $3
Water (I used distilled water for fear the chlorine mine kill the plants) $1
You can easily substitute anything but the bulbs. The water could be purified or treated water (for an aquarium). I would advise against pond water for the micro-organism count, and the smell. The distilled water won't have many of the same problems. I waited to post this until the plant had grown to see if there were any problems with the distilled water sucking the nutrients out of the plant, but I don't see any problems so far.
The taller the container, the more elegant the plants will look. Wal-Mart sells two types of plants, Aponogeton and Lily bulbs. The first is what I used, the second has a different color and shape of leaves. That is about the only difference, they will both work.
Growing from bulbs eliminates the chances of snail infestation. It will also make it easier to setup.