In France (that's all i know about), brokers are mainly web based and their commisions are not cheap. Moreover, you've got some additive taxes (0.3%) as soon as you trade more than 7830⬠(about 500 shares of a 16 ⬠stock).
However, you can short easily (no uptick rules). You can have 5x margin. The liquidity is good, the volatility not as good as in the US.
Actually, the most (french) active/liquid names are Alcatel, France Telecom, ST Micro, Vivendi.
When I began, I traded french stocks but only one month after I decided to trade futures.
Every french daytraders I know trade us stocks only.