We had a customer come in today & recommend a site caled Fictfact.
From their website:
"You read books in series. You want to keep track of what to read next. You want recommendations on what to read next. You want to know when new books are coming out.
"That's why you need FictFact!FictFact is a tracking site focused on book series. Let us know what books/series you've read and we'll let you know what you need to read next and what's coming out soon. Registration is free, so let us know how you like it, and what series, books & authors we might be missing."
We like to read the books in a series in order, so we think this will be a great tool for us!