I'm looking to buy 10-20 BTC.
Can transfer funds into a UK bank or even pay cash if you are local to London.
You can deposit cash into Mt. Gox's account with Barclays:
-
http://en.bitcoin.it/wiki/Mtgox#UK_.28GBP.29There is a site called London Bitcoin Exchange, though there is not much about them yet so if you do trade, perhaps use an escrow.
-
http://londonbitcoinexchange.wordpress.com/You can send cash (GBP) or check to Bitcoin Nordic, by mail, to purchase bitcoins:
-
http://en.bitcoin.it/wiki/Bitcoin_NordicYou might find a local trader (or place an buy order and see if anyone is selling):
-
http://www.LocalBitcoins.comThere are a number of methods:
-
http://en.bitcoin.it/wiki/Buying_bitcoinsAs far as the London Bitcoin Conference:
-
http://www.bitcoin2012.com -
http://bitcointalk.org/index.php?topic=67199.0