What subject are you particularly looking for books about? Just asking for books covers a wide territory. Is it books on magic you want? Or books on Wicca? Or books on divination. Be a bit more specific and I'm sure you'll get lots of suggestions.
without knowing the subject, i could recommend The Picture of Dorian Grey or The Bell Jar, they're nice books [unless you mean 'nice' as in nothing scary, instead of good story]
to get the more common ones out of the way, Scott Cunningham and Raymond Buckland. these are two well known and highly respected authors, even if you're not specifically 'wiccan'. Scott writes from a more 'there's no wrong way' approach, while Raymond is more 'if you're Wiccan [or whatever the subject is] it has to be this way'. in a sense they're both right. if you follow a specific path [say Wicca] then you believe in the Rede and the Threefold Law. if you don't, and your path is more being in tune with the seasons and magical/spiritual world, then you shape your own moral compass. not to say paganisms is a free for all [some choose to see it that way] but with each religion under the pagan umbrella there are beliefs each follower holds as facts of their specific religion. and even if you shape your own path, things like 'magick is a force nature and is bound by the laws of nature' cannot be changed.
lol, random sidestep there, sorry. i personally really enjoyed The Goddess is in the Details by Deborah Blake. [it speaks more about what to do after your year and a day] other books you could read include
Grimoire for the Green Witch by Aoumiel
The Witches' Bible by Stewart and Janet Farra
Magick Potions by Gerinda Dunwich
The Wicca Garden by Gerina Dunwich
Natural Witchery by Ellen Dugan
that's just to name a few. there's tons of books on the occult with very little filter to figure out which is good and which is bad. could you provide us with what you wish to learn about?