Most folks here are probably going to want a few more details to be able to make a recommendation. A few questions that immediately come to mind.
1. New or used, does it matter?
2. Monitor or floorstander?
3. If a monitor will you be using a subwoofer?
4. How much does appearance (WAF) matter?
5. Room size?
Having said that, I'll make a few psuedo-informed recommendations. I am more familiar with with monitors / bookshelves so I'll stick to those.
1. ACI Emerald
http://www.audioc.com/speakers1/emerald/emerald.htm I use these as my surrounds. Very nice midrange.
2. Von Schweikert VR-1
http://www.vonschweikert.com/vr1.html These go deeper than the Emeralds, so they might be a better option if you don't have a sub.
3. Ascend CMB-170 or CMT-340
http://www.ascendacoustics.com/ Not as nice looking, but these have a very good reputation. They are coming out with SE versions shortly.
4. Usher S-520
http://www.usheraudio.com/speaker-s520.html I haven't heard these, but I've seen many folks speak highly of them.
5. Quad 11L / 12L
http://www.quad-hifi.co.uk/lseriesmodels.htm Another one I haven't heard, but it gets good reviews.
I'm sure there are plenty of others, but those are the ones that come immediately to mind. As far as floorstanders goes you are going to probably have slimmer pickings and will probably have to go used. I leave it to someone that is more familiar with that area to make suggestions. Good luck in the search.