Boost .com site ranking in non-US Google

Here is the background: Thanks to my own SEO efforts and some fellow warriors, my .com website is ranking very well in Google.com - I am talking a number of #1 spots for quite a few keywords, as well as top 5 for many others. This is great.

The thing is that my business has to reach global clients. When I do the same Google search as if from other locations (using the Google Global extension), the keyword I am ranking #1 for in the US, I might be ranking #5 for in Australia.

I would like to boost my rankings in these other locations also. What I am thinking may be the issue is this: Perhaps most of my incoming links are from .coms with US IPs, so maybe that is making Google think my site is a narrowly-focused US-based .com, rather than a more global business.

Does anyone have any idea about how I can boost my rankings in these global Googles?

(Warriors with experience and services, you are welcome to approach me via PM if you have a particular expertise / service for this problem).

Cheers

Someone

P.S. I will not reveal the site URL in this open forum, only via PM. (I don't want my competitors to know what I am up to marketing-wise!)