Got my missus a Felt Z95 for ~$675 last year; great entry-level ride - Sora/Tiagra mix. Seems they've discontinued that model though. But have a look at the Felts; conventional wisdom would have it that they're better value than the big boys like Trek and Specialized.
http://www.feltbicycles.com/USA/2010...alog/Road.aspx
Also keep an eye out for '09 model year bikes on closeout - though with Christmas fast approaching they may mostly be gone already.