Beginning Online Share Dealing

I’d like to set up an online share dealing account but need a bit of help choosing one. I’m not sure of the volume of trades/month I will be placing or the amount I’m going to play with. Has anyone any experience?
I think also I’d best play with a real-time test account before leaping in with real money. Are there any good companies that provide this and especially a system that closely emulates the real thing?

http://www.share.com

http://www.iii.co.uk/

+1 for Interactive Investor (iii, above).

If you sign up to iii, you can add shares to your portfolio without actually doing the transaction, e.g. – 500 shares in BP @ £4.5 purchased on X/XX/XXXX and see how they do.
It will show you profit/loss etc…..just remember to take into account the commission cost – more relevant if you are dealing in small quantities.