I do not add a label to my quilt. Since I quilt all of my own quilts, I quilt the info right into the quilt itself. I developed a Logo using the initial of my 1st name + my last name (MRay) and add the current year.
EX. MRay_2014 When actually quilted the M is located higher. The M's last leg becomes part of the R.[ATTACH=CONFIG]478956[/ATTACH]
Sorry this is so rough
I drew this using the Paint program and my 'puter's touch pad. I promise that it looks better on my quilts. LOL Anyway, this give you the idea of what I mean.
I add this after making the quilt and usually in the same thread color as the quilting thread. This makes it blend into the quilt. Sometimes quilts are stolen and this would help identify the quilt to the owner. I don't think many thieves would like to pick out the stitches. Since they are not very noticable, I point it out to the owner, so that they will know where it is located.
My feeling is that is how an artist signs their work--something readily recognized but not distracting from the painting.