Check this thread from a few days ago. I know similar questions have been asked recently, so you could search for more threads, too.
The SCM early readers booklists are great. They make great read alouds with preschoolers, but many of them are good for beginning readers as well.
AO has this list that we've enjoyed many books from:
Frog and Toad readers by Arnold Lobel
Little Bear readers by Else Holmelund Minarek
George and Martha series by James Marshall
Frances books by Russell Hoban
Henry and Mudge series by Cynthia Rylant
Free online beginning readers by Harriette Taylor Treadwell
The 1000 Good Books list has a good selection of easy reader ideas as well. (Scroll down a bit on this page)
Enjoy! But watch out, now I can't get my kids to go to sleep at night because they go to bed with a pile of books! <grin>