I have read a few books that have had this "what now kind of feeling." In fact I read a book with a sequel. I tend to read books with sequels I enjoy having something to look forward too. Unlike the book I am going to mention. "Innocent Mage." It was a sequel, both books were on the counter at the bookstore, so I picked one up and read it. It abruptly ended after 634! pages.
I thought, guess I should get the sequel(my own fault after such a bad read) see if anything happens. After another 700! grueling pages I wish I had that portion of my life back to read a better book.