I would like to add color to art I've drawn myself with a tablet such as this one:
(do not comment on my artistic skills; this was drawn as an example)

but as you can probably see, the body of the fish is not completely closed. I don't want to use a brush and manually fill it in myself (that would give a very uneven look) but if I use the paintbucket the color will leak out of the fish and go everywhere.

I'm completely new to Inkscape and would appreciate any help at all!

Thanks :]

For some of the shapes you can still use . This tool works on the image you see. So if you zoom out the gaps get smaller which may make the tool more effective. Note that the tool has a gap setting also. Read more at http://tavmjong.free.fr/INKSCAPE/MANUAL ... t-Gap.html

As the for the shapes that don't come close to being close, just use or to draw a closed shape beneath the area you want to colour, and give it a fill with no stroke.

Microugly's reply is dead on, but a quick way may be to simply duplicate the paths that are open, use your node editing tool to close them into the shape you want, remove stroke and apply your fill.