The names goes by G or Giza. This is 
How to make an avvie
You must have a basic knowlegde of GIMP or else you won't understand. I use shortcut explanations. I suck at explaning things xDA basic avvie tutorial :) Sorry, for grammar issues. I'm not fluent in English. You may pinpoint it if you like. Maramail :)
Step 1: Image, background. Of course you need that. I'm going to use my character :)
Step 2: Open Gimp. Create a file of 50x50 like so:
Step 3: After that make a background. It doesn't have to be fancy. Since it would cover by the image
Step 4: Next, paste your picture in. Normally something like this would appear in the layer dialog.
What you would do is, right click on the layout and pick "New Layer". The image will auto-deselect after you choose to new layer it.
Step 5: After that click the "Scale Tool"
Resize the image, so that the face would fit the 50x50, not so much small, just right. You would see it, if it fits the avatar or not anyway. :)Step 6: After you resize the image. Move the image, make the face the center of attraction.
Step 7: Use the "Fuzzy Tool"
and select the white part of the image
Hit delete.
Right click it and pick "Layer to Image Size". Merge the two layers.
Step 8: I got lazy, so no screen shot here til end. After merging right click on the background layer and choose "Alpha to Selection". Now go to Select > Shrink > 1px > Ok.
Step 9: While the layer is active. Hit "Ctrl + I"
Step 10: Create a "New Layer" and name it as border
Step 11: On the "Border" layer fill it in black. After that, merge the layers
Step 12: Now, use a font. Preferably a pixel one. Use white as font color. After that. Type in whatever you like.
Step 13: I typed in "Giza's Tutorial" in capital letters. To make the letter visible, outline it. Merge together.
Step 14: Here's the fun part. Animation! Weee! Lol. I use a Orchid color. Because animation is create by frames. What I did is, I use a orchid color and typed in "G" first. Each layer each letter. Are you caught up yet?. Like this:
Step 15: After that, save it. Be sure to save it as GIF for the animation to work or else it won't.
Step 16: A dialog would appear. Simply choose "Save as Animation"
Step 17: Another dialog would appear. Now, you can choose to loop it forever, or it can be played once. I prefer you choose loop. The second there are the gaps seconds between frames. I normally use, 100 or 120. Whatever is fine.
Done! Here my final product for this tutorial :)
Have fun playing with the animation!