GIMP Labels has a (fairly small) list of common label templates (from Avery and others) to help in using GIMP to print address labels, business cards, CD labels etc.
labels.scm gives you:
Create a new image with the right aspect ratio for one label.
Filters/Combine/Make label page...
Once one label is created, duplicate it as many times as desired to make a full sheet (only US-letter currently supported) of labels.
Create a new image sized for a full or mini CD label.
Create a mask in the current image sized for a full or mini CD.
If you have special gLabels templates you want to import, the tarball also contains:
A Linux python script to look for an installed set of gLabels templates and generate script-fu code.
Home page: http://shallowsky.com/software/gimplabels/