As far as advertising your business you have a few options.
You could choose to advertise it yourself online or through papers. You could do this through
Businesses For Sale UK - Sell or Buy a Business for Sale or maybe through the Daltons weekly newpaper which I think has an online edition.
You could also advertise in the property section of your local paper.
When selling off your own back you will still need the services of a solicitor to make sure the transfer goes smoothly.
Alternatively you could find a business transfer agent which is really just an estate agent for the business world. If you google it you will find many. They act in the same way as an estate agent in that they try and find you a buyer, for a fee or commission of course. Very often they advertise in the places I mentioned above on your behalf, or you can choose to not have it advertised so publicly (if for example your staff don't know you're selling and you wish for them to not know for now).
Expect the process to take a while as a buyer will want to take a look at the business, at some stage the books and will probably take them to their accountant and solicitor to see what they make of them. Be sure that you are dealing with a genuinely interested buyer before you start handing over too much personal information.
Also just a thought, The Guild has a classified board that you could maybe advertise on and if you let the geeks on here know in your blog where you are located, you might get some interest.
Hope any of this is of help.
:hug: