ursa: wasn't trying to "get you."

Just making a comment. A problem for me with
ebay is the use of PayPal. I had a subscription to PayPal years ago that I allowed to lapse. When I tried to renew, I was told they needed my social security number which I could either call in to them, or fax it to them. My reaction: "Hello identify theft." So, no PayPal now for me.
Geoff: thanks for the suggestion about Portuguese auctions. I'm a little wary about bidding in auctions outside of the US and Canada. I know that it is already an effort to get stamps from the Lisbon dealer. No fault of theirs, but I have to wire money since the Portuguese banking system does not allow for receipt of foreign checks (probably with good reason). I'm stopping in Lisbon on the way home from a multi-day hike/trek in southern Bavaria. Plenty of uphill walking also in Lisbon, as you know.
eagle79: welcome to the Forum. I've heard good things about the Knoxville club. Another good place for cheap stamps, that are hard to find, might be a philatelic library. The Rocky Mountain Philatelic Library here in Denver is one such place, especially since there no longer are "brick and mortar" stamp stores in metro Denver.
Another option is to do what Floortrader does; buy bulk lots at auctions like Kelleher & Rasdale. Yes, you may get a lot of duplicates, but possibilities for getting shades and other varieties exist.