What are your suggestions for a pre-amp?

What are your suggestions for a used pre-amp under $1000?
System utilized primarily for music. Will likely stay 2 channel with an out for a sub-woofer.

I will have:
-(2) NAD 218 THX amps
- Energy Veritas 2.3's
- Subwoofer TBD...
I'm an advocate of tubes. To my ears, they sound more realistic than SS.

Manley Shrimp would be at the top of my list. If you need a phono stage and remote, Quicksilver Full Function Preamp would be an excellent choice.
Another good-sounding alternative is the Audible Illusions Modulus series of preamps. Often seen here from $700-900 or so. I agree that tubes add that certain something. If you like vinyl, the John Curl phono board (an option in later Modulus pre's) is very nice sounding.

I like octal tube amps, so the Mapletree Audio amps are just so musical to me. The Ultra4 SE is about $900 new, but rarely seen here used. You'd have to ask Dr.Lloyd to add a sub output for you, should cost you $50 additional. I saw a deHavilland Ultra-Verve close to your price range, which is another rich, musical octal-tube pre.

The Juicy Music Peach is also pretty nice sounding, and within your budget.

Hope this helps!
Since you say "will have" I recommend you put together differentially a balanced system. Something like the PS Audio GCC series and a Raysonic 168 CD player. The 168 has a fantastic variable tube outs, so you can just get an amp. But, if you want to incorporate HT then get the GCC
Accuphase c-200

A sleeper preamp. more flexable than any other pre and will surpass the NAD's you have (by miles) and you can upgrade around it, a bargain used. A revelation to your ears.

Research it..