Take a look also at Tymora - there is now a $50/month version. It scans a subset (defined on liquidity + volatility???) of the market (around 2500 stocks??) for a number of predefined criteria, many/most of which are what you probably would be looking for.
I use Radarscreen, and Metastock for EoD and would use Tymora if I were in same timezone, might anyway just bfor the 2 hour overlap now they have the $50 version driven via IB TWS (level 2 etc not 2500 symbols).
There is also tradegopher but i think trade ideas and Tymora's alerts are better. Tymora pulls together a lot of other info from disparate sources. I use my own custom programmed alerts in RS.