Ooh, great suggestions here, will enjoy my trip to the library this week!
Also the Witches of Eileannan by Kate Forsyth, great, strong women lead characters.
I too hate getting part way through a series and finding out the author is still writing so I have to wait for the next book grrr
BUT Isobelle Carmody is my second favourite author of all time, the new Obernewtyn book is great but I had no idea it was out, stumbled upon it in a bookshop a month ago and nearly lost my mind with excitement. She's frustrating because she has three unfinished series on the go and the last Obernewtyn book took 10 years to come out !!!