On being demobilised in 1919 and having no definite career plans, he came across an illustrated catalogue of antiquarian books, published by James Tregaskis of Great Russell Street.
The idea of working in the bookselling field appealed to him, and armed with a letter of introduction he made the acquaintance of Francis Edwards Ltd., and was summarily employed.
In the 1930s Tooley left Francis Edwards Ltd and opened The Atlas Bookshop, just off Charing Cross Road, and started dealing almost exclusively in antiquarian maps.
When The Atlas Bookshop closed in 1936 Tooley started work at the Parker Gallery in Albemarle Street – the firm specialising in military and sporting prints as well as old maps.
In 1946 the management of Francis Edwards Ltd, keenly aware of Tooley's considerable business expertise and knowledge of old maps, invited him to rejoin the firm.
The interest generated by this idea was widespread and led to The Map Collector's Circle being formed in April 1963 under Tooley and David Schrire.