Short answers, pulled from the story.
A Dictionary of the English Language was published on the 15th of April 1755. A folio edition had appeared a few weeks earlier, on the 4th of April 1755, followed shortly after by a second edition issued in 165 weekly parts.
Johnson was paid 1,500 guineas, equivalent to £1,575, by a consortium of London booksellers including Robert Dodsley and Thomas Longman. Notably, the cost of the paper alone for printing the Dictionary ran to nearly £1,600, which was more than Johnson received for writing it.
The first edition of Johnson's Dictionary contained a list of 42,773 words. Johnson illustrated the meanings of those words with around 114,000 literary quotations, drawn most frequently from Shakespeare, Milton, and Dryden.
Johnson took seven years to complete the Dictionary, working from 1746 to 1755 at 17 Gough Square in London. He had originally claimed he could finish the work in three years.
The Oxford English Dictionary reproduced around 1,700 of Johnson's definitions, marking each with the letter J. James Murray, one of the OED's first editors, stated that where Johnson's definitions were correct and his arrangement judicious, it was expedient to follow him. The OED was completed 173 years after Johnson's Dictionary was published.
Johnson's Dictionary has been used by American legislators and courts to establish the original meanings of words in statutes and the Constitution. Because understanding a law requires knowing what its terminology meant to the people who wrote it, Johnson's 1755 record of English usage remains a legal reference in the United States.