I need a set of questions answered in relation to online and offline betting,
The answer must have a clearly stated source. If any clarification is
required please feel free to ask. If you think you can answer just a
few of these please comment and I might approve a partial answer.

In Europe and the UK what is the popularity of the different subject
of betting as % of the market (soccer, tennis, basketball?)? Is their
a difference between online and offline? Is their a difference between
online bookies such as ladbrooks.com to betting exchanges such as
betfair.com? What are the users profile/demographics in the online
betting? What are the users profile/demographics in the offline
betting? What is the average monthly budget of such a player?