Actually, given the way market has been slow and choppy I think a lot of the stocks are nearly untradable. WMT used to be a free point for me every day back in March, it almost felt like they changed specialist in April as I started to lose money in it every day . . . I find it to be more rewarding to trade quicker stocks nowadays, with a bit more wiggle room . . .
The thinner stocks move faster, so risk and reward come hand in hand. Yes given the lack of liquidity you have to take profit quicker, once they drop the BID the next BID is like 20-30 cents away.
Here is a list of stocks that consistently move with their respective indexes . . . That said, I recommend new traders to start with tier 2's in those sectors (for example, in SOX you would want to start with AMD/NSM, in XBD you want AGE/BSC) . . . they don't gap down on news and they lag a bit behind the sector indexes, easier to trade and typically reduced damage if you are wrong . . .
The most important skill you can ever have in NYSE trading (especially scalping) is tape reading. The specialists have some of the nastiest tricks to take your money, on top of chart/indicators you absolutely MUST learn to read the TOS, unfortunately there is no real book/tutorials out there that teaches you tape reading, it will come from time and experience to be able to get in near the bottom and get out near the top.
Good luck . . .
S&P/Dow: GE/IBM
CYC: MMM
SOX: ADI/IRF/TXN/MU
BTK: DNA/CRA
OSX: SLB/BJS/CAM/SII
XNG: APA/APC/EOG
OIX: AHC
CEX: DD/DOW/PPG/FMC
XBD: MER/MWD/GS/LEH
IUX: MMC/PGR
DRG: LLY/JNJ/MRK