If you try to charge people for your share tips/advice; without being regulated (England) Can't comment on other countries;
ie not qualified to give investment advice, then the FSA will come down on you like a ton of bricks. They close down and prosecute on a regular basis, that most people just don't get to hear about.
Maybe because they are such clear cut cases. Not authorised = can't charge = prosecution.
However if you set up a site/newsletter and put in a disclaimer that this was for fun. testing etc, you could get away with it. (note the could), but then you wouldn't be able to charge would you.
And I think, though not too sure, that you can only give investment advice to actual 'clients' of yours to begin with.
As said above though, e mail or phone the FSA direct and ask them.
The regulations in USA for example appear to be more lax and various sites abound. Dependant on your view, we are either lucky or not that the FSA are there to (supposedly) protect us.