In November 2014 there were 35 Clay Pipe listings on eBay. At the end of the same period 634 had been recorded by the Portable Antiquities Scheme. EBay lists the equivalent of 5.5% of the PAS each month and would take 18 months to sell the same amount of artefacts.
+RARE! Pre-Columbian 300-900 AD VERACRUZ Clay Tobacco Smoking FACE Pipe
3 vintage clay pipe bowls without stems
14 Old clay pipes dug up or found on fields around North shields one 1690s full
17th CENTURY CLAY PIPE SECTION. NICE CONDITION.
18TH CENTURY CLAY PIPES CIRCA 1730 – 1780 ,SOME WITH MAKERS MARKS
19 C SAILOR FIGUREHEAD CLAY SMOKING PIPE PAINTED GLAZED AFRICAN
25 BRITISH TAVERN CLAY PIPES 1650-1880 ALL DIFFERENT DUMP DUG CONDITION
A COLLECTION OF 25 CLAY SMOKING PIPE BOWLS VARIOUS CIRCA 1700 TO 1900
A vintage long South sea islands wood carved pipe, clay bowl
antique clay pipe display case
Antique Dutch Tabacco clay pipe 18th century with stem
Antique UK Clay Pipe 30 Lot 1830 Bowl Dug Up Rare
British Found – French Ornate Clay Pipe 18th century
CLAY PIPE FRAGMENTS
Clay Tobacco Pipes – 17th-19th century – Metal Detector Finds
Colonial Fredricksburg 18th Century Relic Ceramic Clay Pipe Stem Artifact Lot 2
FRAMED GLAZED DEEP MUSEUM DISPLAY CASE EXAMPLES OF EARLY CLAY PIPES TOBACCIANA
Nupe Clay Pipe Nigeria Africa
old clay pictorial smoking pipes
Old Tobacco Clay Smoking Pipes & Original Crate
victorian clay pipes in frame
Vintage Colonial Williamsburg Mounted Handmade ‘1800’s Tavern’ Style Clay Pipe
All map data ©Google
Public Archaeology 2015 
Out of interest, is there anywhere in England where we might not find clay pipes?
Short answer is, don’t know. I haven’t had time to map any of the objects for sale. If you fancy it, the full dataset is available on the 1 April post.