Any of the local scrapbook stores would be a good place to check - most have both 8x11 and 12x12 paper in stock, so you could select what you want and then trim it to suit your needs.
My favorites:
Cool Scrapbook Stuff (Poway) Ever After (Vista/O'Side Area) Scrapbook Your Life (Point Loma)
Re: Specialty Decorative Paper
There is one up in the Carlsbad area.
My favorites:
Cool Scrapbook Stuff (Poway)
Ever After (Vista/O'Side Area)
Scrapbook Your Life (Point Loma)