I tend to approach collecting like cataloging a small museum, so my advice is detail-oriented. First, identify the exact edition you want—first edition, first printing, cloth-bound, etc.—and note the ISBN and publication details. Use precise searches on specialty marketplaces like AbeBooks, Biblio, and even rare book dealers' sites; many allow filters for "signed" or "inscribed." Auction houses can also
be useful for rarer signed copies; set alerts on sites like LiveAuctioneers or Invaluable if you’re patient and ready to bid.
Offline, cultivate relationships with used bookshops and dealers in your city. I keep a spreadsheet of contacts and the titles they mention, and I’ll ask them to notify me if 'Northwoods' appears signed. Facebook book-collector groups and local collectors' forums sometimes surface trades or private sales—just vet sellers carefully and request provenance or multiple photos. When a seller lists a signature, compare handwriting samples from known events or the author's social posts; it’s a nerdy habit but it protects you. After a few purchases you’ll get a feel for reputable sellers versus sketchy listings, and that confidence makes future hunts smoother. I still get giddy seeing that flourish of the author’s pen.