Based on quickly reviewing the user stories I have come up with a short list of entities the system should support:
Doesn't look too bad. User stuff (membership, roles, profiles) will be handled by the built-in providers for the most part. The vendors are mostly just for searching and linking to sites so people can buy the items. The reviewers are for searching and linking to sites so users can read reviews. I think the wishlist is where we will have most of the heavy lifting, which makes sense since this site is all about the wishlist.
In the next installment I will identify some of the attributes that I think each entity will need.