Set up a limited company

I currently trade as a sole trader but want to change to a limited company. I have a dormant ltd company set up but have never traded under it. I would like to be set up as a limited company but don't know how to go about it.

Preferably i would also like the same person to manage my accounts that will be involved. I currently have an accountant for my sole trader accounts so guess once set up i can stop this service?

Advice and quotes welcome.