My top three are Celestial Studios Vogue, Fleur, and Gala. That's a (CS) Vogue in my
SLU avatar.
But, really, it depends on personal taste...there are a lot of well made skins out there which look perfectly weird and un-Ann to me when I try them. You may be new enough not to have a solid idea of what your av 'should' look like yet, so all I can say is demos, demos, demos!
