Agree except for recommending SJD. They are a good accountancy firm but when I was with them they would only do my accounts through a really horrid excel spreadsheet. This time round I've gone with http://www.nimblejackaccounting.co.uk/ who bundle an account with freeagent (which is probably the best contractor accounting package out there) AND the set up of your limited company in their monthly fee.

If you're going to go contracting don't bother with an umbrella company! It's absolutely ridiculous how tax efficient you can be as a limited company (especially if you can set up you significant other as a director). You're looking at just under £40k per director completely free of personal tax and NI if you set it up right. You still have to pay corporation tax and some VAT on that amount and there's all the overhead of managing the company, but it's seriously worth it - especially with a good accountant!