Okay, so I tried to take Joe's suggestion and go back and redo the rivers a little (and add a little noise to the ground). I just fuzzed up the edges of the rivers with a soft brush, and thinned them out. I put a b&w gradient on a plasma noise and overlayed it over the ground layer to provide some additional noise on the ground cover. I also added an additional terrain label.

Click image for larger version.  Name: Practicing techniques 1-part3-rivers.jpg  Views: 80  Size: 85.8 KB  ID: 4277

Then, I started in on the title. Here is the final output for that. I noticed that I couldn't follow RobA's instructions exactly because, given the order he used by applying the mask to the gradient/curve layer over the title label first and then distressing the edge of the title lable left some unusual artifacts along the edge of the title label. By removing the mask on the gradient curve layer, then alpha-to-selection on the new, distressed-edge title layer, and using that selection for the mask on the gradient curve cleaned up those artifacts.

Click image for larger version.  Name: Practicing techniques 1-part3-title.jpg  Views: 62  Size: 92.2 KB  ID: 4278

Finally, the border. I didn't try to do a legend or compass rose.

Click image for larger version.  Name: Practicing techniques 1-part3-final.jpg  Views: 105  Size: 103.4 KB  ID: 4279

And that's that. I think I've learned enough about GIMP to give it another go round and to be a little more adventurous in what I try next time round. I started the thread with a second set of coastlines begun using RobA's tutorial, so I'll see what I can do with that one now.