OK, I love the concept of fantasy, but I hate 99% of what's been produced in the genre.
-Nothing long or strongly epic, which are the bad side effects of Tolkien's influence. I want something that's over in one book (that could be an anthology of short stories BTW),
You are greatly limiting yourself here. I can't think of much decent fantasy that's over in one book. So, since your constraint is irrational, I will do like most others have and ignore it.
The only one-book fantasy novel I'd recommend is
War of the Flowers by Tad Williams.
*
A Song of Ice and Fire by George R.R. Martin (vol. 1 is A Game of Thrones) - Seriously, it's too amazing to ignore. Best fantasy by far, and realistically medieval too.
* Some have mentioned
The Assassin's Apprentice by Robin Hobb. I'll second it and add the
Liveship Traders and
Tawny Man trilogy by the same author. It's better to read these trilogies (9 books total, but the series is finished) in order, to fully appreciate how everything ties in. Plus, you'll feel less depressed if you read the end of the Tawny Man trilogy than you would have been after the Assassin books (which has a very sad ending).

The books aren't overly huge, so it can be read quite rapidly.
*
Memory, Sorrow and Thorn by Tad Williams. A finished series also, if it helps.
While this stuff isn't over in one book.. Try Robin Hobb's "Assassin's apprentice" series. Very relaxing-bath-and-cup-of-tea-esque.
Heh, yeah. I always get an urge to make myself a cup of hot tea with honey in it when reading her books, especially the Tawny Man. I swear, everytime characters sit together for a meal or just get together before going to sleep, tea is involved.
too bad about the 'no epic' rule.
if it hadn't been for that rule I'd have recommended:
'Song of Ice and Fire' (like many other forum dwellers

)
Robin Hobb's series: Farseer trilogy, Liveship trilkogy and Tawny man trilogy.
if you want to go for hack and slash fantasy:
some of the Drizzt books, or the Arilyn Moonblade books
I like your taste, sir. For hack-n-slash D&D stuff, Elaine Cunningham's books are quite superior to the norm.
As a devout Jordanite I consider you a Darkfriend. (written as a joke)
I love the Wheel of Time series. (sincere)
I keep on preaching the merits of Rand and his friends, but nah..
Um, I recant the above. *spits on Jordan*
Seriously, I could rant for hours at how bad it is, yet I keep reading it, because I'm too far in the bloody series to quit now. Gah!