A look around this section should give you what you want, dont be deterred by a slow response but this question seems to get asked a couple of times a week!This thread
has some good stuff in it, did you mean online or an actual book?
This is a very good PDF dictionary for your PC, its not comprehensive but its a good start and easy to use.
Some online dictionary/translation tools:
to letters and words on video. (a lot of hard work done by someone on here, nuff respec!)
polish.slavic.pitt.edu - A much praised site that should help with everything else.
I started with the Pimsleur audio program, good for your MP3 player to learn anytime/anywhere and will get you started on the basics and with pronunciation.
It isnt cheap... unless you find it in a torrent somewhere.... *innocence-whistles*
I've only been learning for a couple of months in the precious little time i have to spare, but last night i had a great chance to test myself and it felt great to be able to communicate! (albeit on a very basic level so far!) Good encouragement to carry on.
Of all the links i give above, i have found the best place to come is here!