Baen Books ebook store has always been a good and hassle free place to pick up ebooks for my Kindle and iPad.
They have the complete collection of Lieber's Fafhrd and Grey Mouster series for $6 each or $35 for the whole set.
Also they have the original Paksenarrion books by Elisabeth Moon. One of the best novels about a D&Dish world to date. The author thinks about the underlying reasons for why things are in her world and relates to the characters personal lives. It makes a for a great read.
You can read the first book Sheepfarmer's Daughter for free. Note that she is currently writing a sequel series to the original Paksenarrion books. Interestingly they are not about Paksenarrion but rather about the impact her action had on the people around her.