I've made a  background on GIMP for my text-game. I want to make it so that it can scroll with the player's text without showing any weird lines where the image borders are. I have basically no experience editing images so I was wondering if there is an easy way to make it work?

Here is what I've got so far..

I used this tutorial to make it. (I went with a darker color)

Seamless textures is what you’re looking for.  :^)

According to the GIMP documentation, there’s already a built–in plugin.

EDIT:
And there’s a more advanced plugin here: http://registry.gimp.org/node/28112

The healing tool in gimp allows you to get rid of seams. Photoshop has much better tools for this and is one of the main reasons that I even have Photoshop.

Thanks guys.

One trick(in photoshop or GIMP) would be to use an "offset" command.  Offset by half the image, and the seams will be crossing in the middle of the picture.  Then you can paint then however you want(maybe using healing brushes and the like).  Then, if you want, you can offset it again, or not, and either way the thing will be seamless unless you accidently paint right on the edges when you are removing the seams.