I have used
www.duport.co.uk to register companies in the past - they have provided a very good service - they have quite a few ready made companies that can be useful as they are older.
I have also used
www.incorporateonline.co.uk - they also provide a good service.
VAT registration seems to take ages these days - especially the Wolverhampton office - they were sending out a letter saying that they take 12 weeks minimum to reply to a VAT application - the VAT application form is available on the HMRC website and is quite straightforward.