Have you tried hanging around outside your local tip? Admittedly, you end up loking homeless and disreputable, but people throw some near new things away these days.
And what's your local equivalent of car boot sales, flea markets etc?
Also to consider, it must be the same the world over, police recovered stolen property auctions. Not everything can be traced back to it's owner. The nearest one to me sees up to 10 bicycles going as a job lot for £100.