For the coins and amounts:
http://www.bignell.uk.com/english_currency.htm
For what it's equivalent too
http://www.ex.ac.uk/~RDavies/arian/current/howmuch.html
Once you've got the names of actual coins you could try a google image search for what they look like.
As far as I know the alphabet was 26 letters, though anyone with a classical education was liable to think of i and j as much the same thing.
Books - about a 50% literacy rate or a bit more, but much better at aural memories than we have as a result. Bibles, prayer books, also printed ballads and stories, scandals, polemics. Important announcements nailed up on church doors, which were the parish noticeboard. Important sermons were printed.
Theres a specialist printing trade library here:
http://stbride.org/library
Emma
<Added>The Bank of England has a museum which I think has currency in it. Can't remember if the Royal Mint does, which it ought to, but their website's pretty feeble.