I know of the chap behind scentsamples.uk.com as above.
Bloom also have a great reputation.
If you’re around London it’s apparently worth your time to visit Jovoy, they do great scents and are generous with samples from what I’ve seen.
Another one if you’re looking specifically at creed fragrances is tomscreeddecants.bigcartel.com
I’ve chatted with Tom (behind this site) before and bought decants from him and he’s been a pleasure to deal with.
Otherwise, ask around! Some people here might have the scents, and means, to give you samples.
What is it you’re looking for?