Hi,
I am pretty much a noobie, but for the past 4-5 months, I have been using the "My Watchlist" functionality on portfolio.rediff.com.
I get emails whenever a stock passes a threshold that I have set. It seems to work fine up till now. It doesnt seem have a limit on the number of stocks that can be added. Maybe they charge after the number of stocks cross 100 or something, but as of now, its free.
A software may help with immediate alerts and be more responsive.
With regards,
Anupam