In a special wealth and personal finance section, the New York Times offers advice for beginning collectors. The story is more focused on the decorative arts but it applies to any collecting categoy:
Like many new collectors, they were faced with a series of questions: Where to start? How focused should their collection be? Should they shop at one or two major auction houses or include country auctions, too? Should they hire an expert to help them vet the objects — for a fee — or rely solely on their own instincts?
Whether collecting pocket watches, rosewood divans or Sèvres porcelain, seasoned collectors and auctioneers alike say the most important requirement is to find something you love.