I am working on .uk and on .au projects and i have done off page worked for these projects in Google.com but from somewhere i heard if you are working for .uk and .au sites then you should target local search engine like you have to work on Google.uk and Google.au for more better result. So now i want to know something more on this topic is it true or false.
It depends on what do you want from your project. If you want to make sales from the site in the specific region of course it would be better to target it in this region. Because in the whole world there are too many competitors even if your site is in vacant niche of some regions.
But if you want to have more visitors from all over the world it is not neccesary to target your site for local serach.
Definitely, As per Your post, your targeted countries are .uk and .au so you should focus on Country Specific activities like Local listing, Find country Specific Blog Sites. And Start doing Work on it. Visit Schema DOT Org. Schema will Helps you to find the Related Category and put that code in your coding which help Google to find Locally, hope it helps.
[FONT=Verdana]Have you read Google’s guidelines on geotargeting?
http://support.google.com/webmasters/bin/answer.py?hl=en&answer=62399[/FONT]
If you want to get traffic from specific region then it is better to target that specific region. Because what happened, if you will targeted specific region then there is a less number of traffic compare to all over the world. So i suggest to target local sites.
To all involved - please read the full OP before posting. I’ve had to clear out a lot of posts for people who didn’t read the whole original topic and question…
Austin - read the link that TBear posted - it’ll point you in the right direction 
Yes, person told you is correct. If you are working on a specific country then you have to target that country only you can check in .com also as its global. But for good results you have to target that country only from where the project is based.