Best bookshelf w/ ribbon tweeter under $2000

The stiff Breeze from vapor audio. I think it runs $1995, two custom paper in an MTM configuration with a time aligned stepped baffle sandwiching a RAAL tweeter. I own its big brother the Cirrus but I heard these when picking up my speakers at the owners house. Pretty phenomenal.

Look for a pair if Red Rose monitors

Second the recommendation of the Vapor Audio Stiff breeze.

04-12-13: Mapman
Goldenear AON (larger model) at ~ $1000 designed for good sound and value should compete well up to $2000 otherwise.

+1!

The Aon3 is a phenomenal speaker at $1K. It has all those great hallmarks of a good stand-mount--resonance-free, transparency, great imaging and soundstage, but much less of the downsides, as it's also 90dB sensitive, dynamic, and has bass extension down to the 30's.

Their folded ribbon is a revelation in how much overshoot and ringing harshness we've become accustomed to in conventional pistonic tweeters. This tweeter gives you all the treble speed and extension (out to 35 kHz) with much less of the artifice of sound reproduction. This tweeter type shows up in some pretty expensive speakers including the Helix, Whisper, and Focus (top line) models from Legacy Audio, Martin-Logan's Motion series, and the $7K/pair ADAM Audio Classic Mk3.

If you can find them used, consider a pair of VMPS 626 JR's.