yakboomer,
It is hard to answer your question accurately. It has been a combination of things, but primarily I rely upon the traditional, high standard mail auction houses. Eastern, Gary Lyon, Bow City, Vance, Maresch, Cherrystone, Apfelbaum. Montreal City Stamp(?) and a few others. Websites tend to be hit or miss, and not a bargain. But I have used several of them, and
ebay sometimes. The problem that I find with websites and
ebay is the lack of integrity on accuracy. For example, I just bought a moose #117, VF, NH--but it was not #117, but 117b (slightly different brown). Same with say the comment above by Coriandre on 53-54-55: if you were to buy them from
ebay, how do you know that they know pale blue from the others? This is why I trust the auction houses. (Although even then, sometimes I have returned stamps that were not NH).
Generally, I have found if I am patient and do not overbid, then I can find good deals.
Historically, way back--I would also go to stamp shows and there you can find really good deals in my opinion. I have recently gone to a few of them; but for Newfoundland and living in California, the pickings are slim and not for me because I have a deep Newfoundland collection and rarely find ones that I don't have.
I've never tried local dealers.
I would like very much to hear from others on the board about places in Canada to visit; because I fancy and dream of a trip to Halifax or ? and assume that I would see gobs of Newfie stamps and covers. Anybody got some suggestions?