1) As I mentioned below, I like all of Terry Brooks' work. Start with the first 3 Shannara, but it gets much better from there. I think it goes:
-Sword of Shannara (3 books)
-Heritage of Shannara (4 books)
-Voyage of the Jerle Shanarra (3 Books)
-High Druid of Shannara (3 Books)
He's taken two detour series: "Magic Kingdom" and "A Knight of the Word" - both are good, but his writing was much more refined by the time he started "Knight of the Word".
2) Terry Goodkind - Sword of Truth - as people say, it hits a real lull after book 4-5, but sort of picks up again at the final trilogy. Throught, the stories are interesting, he just has an annoying tendency to get side tracked with personal philosophy for 50-page spurts. Still, a fun series overall.
3) Jim Butcher - the Dresden Files. This series is similar to brooks in that the writing gets better as you progress through the 12 book (and counting) series. It'd urban fantasy, and generally quick moving and action packed, if not exactly a masterpiece of prose. Definitely very entertaining.
4) David Drake - Lord of the Isles. This series suffers from a similarity of plot from one book to the next - but the characters are interesting and the setting fun. There's like 10 - not the highest on my list, but some good reading here and there.
5) Robin Hobb - "Assassin" trilogy, subsequent "Tawney Man" trilogy, and the "Liveship Traders" trilogy in between the two - all entertaining.
I could go on if you want more - just ask.