Hi, Most of the times when i check the google webmaster tools for my websites postion, some of them are reported to be at number 3 or 8 for my main keywords, but when i google search the keyword, sometimes they are no way to be seen. Its very random.
You should look at above right and see the timing they pulled. The earliest is "Last 7 Days". If so, the results you see is the result form 7 days ago and not present.
Yeah, better to not rely on that information in GWT. The best way is to check your ranking in actual SERP, mostly in the country you are targeting..
Actually Matt Cutts touched on this a little while ago and he said that tose results also include google images and a few other factors, so its not always as clear cut as it might seem. Location can be an issue as "gl=us" for USA results in google.com is not included, so when you are outside the US, you will get different results to US searchers.