LP Reads loves Bel & Bunna's Books in Lafayette (near Patxi's). They provide kids with well-curated book lists targeted at their general reading level.
You can also look to www.goodreads.com and make LP Reads a friend. There are a host of shelves and books organized by grade level and subject areas for you to consider.
Another favorite website for researching what to read next for the older grades is Storysnoops.com, a site started and maintained by moms who wanted to be sure that the books their maturing children were reading were age appropriate. They have fantastic reviews and lists that can help you populate your “To Read” queue.
Lastly, and certainly not least, be sure to check out our wonderful LP and Moraga libraries