Publishing in 1995... The economies of scale in printing at the time meant that you had to print 750 or 1,000 copies of books to get them cheap enough. You registered the books with Whitakers on a hand-written form. You produced a basic advance information sheet for your repping company four months in advance and they then visited lots of bookshops, including branches of national chains, which your trade distributor supplied in quantity at 35% discount. Warehousing was free as the distributor made enough on commission. Novels were £7.99 and more academic books were £9.99.
Publishing in 2012... Nowadays you print digitally, with it being economic to print even 300 copies (or 100 copies if you don't sell them through bookshops), which is just as well as sales are fewer and you need to keep your warehousing costs down. You register the books and produce information sheets seven months in advance so that your repping company can visit the head office of a couple of chains and a much smaller number of independents which mostly buy from wholesalers at 50% discount in small quantities. Warehousing costs 10p a book per annum. Novels are £7.99 and more academic books £14.99. And then you register the books with Amazon (who will later buy at 60% when people order the books), assorted library suppliers, write blog postings (as do the authors), write about them on facebook, put them on Good Reads and organise reading tours if you can. And make eBooks.
That sound you hear is me, whistling while I work.