。
Books are now within anyone's reach.
Literal
Books [topic-は] now-[at-では] anyone [to-にでも] hand-into-enter.
手に入る (literally 'enters the hand') is an idiomatic expression for 'to become available / to be obtained / to be within reach.' 誰にでも ('to anyone') uses the universal-person construction 誰 + に + でも. 今では ('these days, nowadays') combines 今 with では (temporal 'at this point'). An observation about the contemporary ease of obtaining books.