Has anyone read either of these series? They are both really good! You can get them at an online Christian book store, or at a Christian bookstore anywhere...
If you plan on reading them, I reccomend starting with the Christy Miller series first - because the Sierra Jenson series sort of continues on from the end of the Christy Miller series. They are written by Robin Jones Gunn, and I have a link to her site which is located on the sidebar of my blog.
Happy Reading! And if there are any books you enjoy, please share with the rest of us - I'm a huge fan of reading!