Multiple sites linked to one ecommerce database.

Try linking multiple sites:
John's 8 Jewelry Web Sites
JewelryWoman.Com
CRCreations.com
CRCreation.com
DesignsJohn.com
DesignsByJohnInc.com
EquestrianJewelry.Info
PetJewelryDesigns.Com
JewelryByCerutti.Com

to one catalog http://crcreations.com/catalog/.

SEO for eight web sites can have eight seo themes, i.e. sports, religious, nautical, et.  Each with its own key words, links, et.