Ramrob's correct about the $25k, but if you're short of the initial capital, you can look into any number of private equity trading or Prop firms.  A few to check out would be:
1.  VCM Trading
2.  Worldwide Trading Capital
3.  Harmon Trading
I've seen good reviews on all three and you get full daytrading access with only $5k and they'll usually give you alot of extra buying power.  A friend of mine's at WTC and he put up $10k and gets $100k for daytrading.
If you've got the $25k to daytrade, then I might check out Terra Nova or Scottrade.  Both are pretty low priced firms.  On the education side...its all about technical analysis!