Teri, if a stock attracts your attention because the price has been rising fast...you probably missed the boat.
The real risk/reward game if you want to "play" is looking for the ones that have recently come down hard and haven't rebounded yet.
I like to keep my eyes open for stocks that get hammered because of a single bad event, e.g., a bad quarter. A fast growth company with premium priced stock will have its stock price hit hard when they stumble. But one quarter usually does not spell disaster, and unless there is something fundamentally wrong with the company, you can often get a high return on your investment if you buy near the bottom.
One potential play is Netflix (NFLX). It is high risk because their are very tough competitors trying to crack the market, but the stock was recently punished hard due to a price war sparked by Blockbuster and WalMart. But, they are still the leader. And, as a customer, I can testify to the quality of their service. Check the link below for their six month chart.
Another: Krispy Kreme (KKD). I don't like this one as much because I never believed they should have been so highly valued in the first place. But the stock got crushed and if you've got "patient money," it may slowly rise back to respectibility in the coming years with careful management. Big risk, though, because of their accounting and franchise buy-back practices.
Don't use the rent money on these.
If you want diversity, try the Legg Mason Value Trust (LMVTX). This mutual fund has an outstanding history that somewhat mirrors the philosophy I described...they buy stocks that are under-valued for whatever reason.
http://finance.yahoo.com/q/bc?s=NFLX&t=6m