Smokingpipes.com is the largest tobacco dealer with the most comprehensive inventory that I know of. They are also prompt and accurate in filling orders and answering any questions you may have, and first-rate on customer service. For direct personal interaction, I'd check out the largest brick and mortar pipe shop near you, if any; pipe shops are few and far between, but usually worth visiting for direct in-person interactions.
For other questions and information, you might want to try posting here. Be specific and detailed in asking so people can come up with useful answers.