Highly recommend Goodnight Moon by Margaret Wise Brown.
When I first got it I thought it looked terribly old-fashioned and garish with the colours and thought the rhyme was just silly. But I'll tell you, my twins really took to it. And as I started reading it to them I could see how it "worked", and I've fallen in love with it. I had the thing memorised by the time they were one, I had read it that often. At 22 months they still like listening to it.
I've found lift the flap/peekaboo books worked well from when they were around a year. Dear Zoo is great for that, and DK has a series of peekaboo books that are good (Playtime Peekaboo, Bathtime Peekaboo, etc). The "That's not my... Puppy/Plane/Kitty/Lion..." (there are loads of different titles) are excellent. I also read them Each Peach Pear Plum, but they appreciate it a little more now that they are that bit older.
I don't know what country you are in, but I was given a subscription to Babybug magazine (it's an American publication although mine is shipped to me in the UK), and that is also excellent for a variety of baby/toddler geared stories and poems.