Welcome to the Q&A Forum

Hi Paul, As you already know there are a couple of ways to approach this. Opinions will vary, but with the details you have given I would be tempted to do as you originally thought, keep building links from US based sites. There must be some US based blogs, review sites etc that cover your software field (?), those would be the first place I would look at for getting some more relevant US links. Keep in mind that not all .com sites are US oriented so even though you say you have more US links than UK, if this is only based on the domain then it might be a bit more complicated than that. You have not mentioned what your keywords are, but software type keywords might have some pretty different keyword difficulty scores between the US and the UK, which might account for your #1 ranking in the UK and nowhere to be seen in the US. That being said, since you are ranking in both for other keywords that is an indication that ranking in both is at least possible with the setup you currently have. If you have not done so already, it might be worth putting a news page or a blog post on your site about the expansion into the US market. If you run a blog then I am sure there are some other content ideas you could come up with that detail US specific data for your particular software field which would give you some nice content to use when approaching people for links. Hope that helps!