I practice caution when I encounter advisory sites which ask for money.
A proven analytic calculation for stock prices is Relative Strength Index (RSI):
When I analyze a stock, I do the elbow-work myself.
I doubt that relying on buy/sell indicators from another trader is wise.
My site, StockBeaver.com, sorts stocks by RSI in a simple table.
Also the site shows you SQL you can use to correlate past-RSI-values with past-gains.
In my opinion, the best time to buy a stock is when it has a low RSI value (below 20).