Not very informative... Ok op, for the UK submit to uk article directories and get links from UK websites relevant to niche. Don't forget to get UK web directories. For the US, target us article directories, web directories etc. Using a solid base and start slow, say 10 links per day, change keyword so not all same keyword points to home page - looks too un natural.
No or little link building! Develop content where you mention the term US, UK, location name etc.. and you would rank..