Titles of British Lords [closed]

In an old episode of The West Wing, a British Ambassador is referred to as "Lord John Marbury". Ignoring that once he became Ambassador he'd be Mr Ambassador, what are the possible correct addresses?

My reasoning is that a friend criticised a newspaper which used the form "Lord Firstname Secondname" saying it's supposed to be "Firstname Lord Secondname".

For example, with Lord Coe — or Seb Coe —, his wife is said to be "Carole, Lady Coe", but assume that's just the different names options (as there's a comma)? It's not explicitly stated that there's a correct way to use his (or her) full name, that I can find online.

I tried using the West Wing episode as an example, but they pointed out that it's an American show. Indeed they get other details wrong, like saying two Commonwealth ambassadors met (when ambassadors of Commonwealth countries are referred to as High Commissioners when dealing with each other).

Lord can be used before a forename and surname as a courtesy title for the younger sons of a duke or marquess (Debrett’s). A style such as George, Lord Byron is also found, but I've been unable to identify the circumstances in which it is used.

Not sure if this is what you mean, but I found this on Debrett's site (Debrett's is the authority on titles, forms of address, etc.):

I am a little unclear as to the correct form of address for a peer - when should the person's first name be included? I am referring specifically to Lord Puttnam of Queensgate. Many people address him as Lord David Puttnam but I would say that David Lord Puttnam would be correct. AR Lord Puttnam can only be addressed as Lord Puttnam. The styles you suggest (Lord David Puttnam and David Lord Puttnam) are both incorrect and should never be used!

Nor is it correct to refer to Lord Puttnam as Lord Puttnam of Queensgate. The 'of Queensgate' is his territorial designation and is not an integral part of his title. See Life Peers

Other parts of the site may also be of interest.