Are you going to be doing it as a student placement, or as a normal employee?
You'll need to talk to the embassy about your working rights and tax etc.
If it's going to be as a normal employee, check sites like
www.jobsearch.co.uk or
www.jobserve.co.uk
Contract work might be the best to look at.
Most places will need a month's notice to leave, although unless they can prove they've lost money from you just walking out, there's nothing they can do to stop you, and they must pay you for the work you've done.