I use Nordnet, an online broker found at www.nordnet.se. I think the Black & Scholes formula is the one more used, but am not sure. As for website in english, that is a hard one as all I can think of are in swedish, however there is some basic info here:
Homepage for OMX group: www.omxgroup.com
What do you currently trade? Where are you based?
Homepage for OMX group: www.omxgroup.com
What do you currently trade? Where are you based?