Local Business Directories

I've never paid to be in a directory. There are plenty of free ones out there. Try industry specific directories first, also directories that are specific to your community.

I don't really know how beneficial a paid directory is but I'm sure there are lots of free of charge quality directories out there which can help you advertise your business on the internet. To choose the right directory ask yourself what's the purpose of being listed in a directory?
I would recommend directories that are constantly monitored by moderators (unfortunately many of them are automated) they are responsible for filtering out junk listings, spammers and witchcraft, pornographic, harassing content. Make sure you post your business where your clients can review you. Reviews are highly valuable, 60% (if I'm right) of potential customers will choose companies which were reviewed by other clients . And accept negative reviews as well, try to react in the most friendly and professional manner, that will make you trustworthy

Do we have a list of UK business directories?

Trouble is, you then get spammy long lists of web directory rubbish

With shameless bias, I'd have my selection as:

Us - obviously

uksmallbusinessdirectory.co.uk - professionally run by TJ
freeindex.co.uk - no brainer

Then you have a choice, there are the standard ones, thomsonlocal, scoot group, yell etc, but you might as well as sign up with 118information.co.uk who over time will propogate your details across 100's of directories. They also now own Thomsonlocal (or the parent company does, Market Location).

Next year, there will be a new option, which should make life a lot easier for UK small business owners, with a huge reach of millions of monthly local visitors. But its still in the planning stages, so watch this space! Shall tell more when I'm allowed

Which directory we use:
# Number of Backlinks according to google?
# Page Rank of Home page?
# How Many Pages Indexed in Google?
# Maximum ages of domain?
# High Domain Authority (DA) of Domain?

I thought cyclex was a good option for a cheeky backlink but it's no follow, as it Thomson. Better to stick with quality rather than quantity.

I don't think signing up to business directories is a good back-link gaining attempt, especially nowadays. It can be beneficial for your to list your business on them, but only if you share quality content. Keep in mind that users will search the web for your services and products, and if they find a poorly filled company presentation profile, will not have any confidence in your services or goods.

..and we are also nofollow.

The whole back linking train of thought needs to be adjusted. Times have changed and moved on. Links are still very important, but its the type of links.

Old style web directory links, where you listed yourself on hundreds of script generated directories are worthless, and will now do you more harm than good.

Last May Google quietly changed the rules with directory links, which is why most major directories are either no follow, or hidden behind redirect or javascript. But, directory listings and links are still very important.

eg, Generating direct traffic and leads. Building trust, such as allowing positive reviews across multiple sites to build a positive perception of your business. Allowing you to sell yourself as users get more savvy and do their own due dilligence and research on your business.

Plus one of the big reasons in recent years is Citations. Directories are used as a major source by search engines for citations or NAP format (Name Address and Phone Number).

Especially as the web heads into a more structured data world, directories are used as data reference points to validate business credentials, which can establish local ranking factors.

It's a whole topic in it's own right, but just adding the point here, that it's time to think beyond simple links, and follow and nofollow.