When you buy (even free) an eBook from Amazon you can choose in a "Deliver to" drop-down list to "Transfer via Computer".
There are many other eBook sites, like ManyBooks & FeedBooks, where you can download to your PC, just like any file, in many formats.
1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU BB => 2010: Orange 16 Meg LLU BB