You are not being paranoid. Every time you enter a term in a Google Search Box it is saved. It is saved and utilised. It may be shipped to a Government Agency and you become a ‘person of interest’ but is usually sold to advertisers so that you can be targeted.
That is why if you use Google to Search for hemorrhoids you will find every other Ad for some product which purports to cure/prevent/treat hemorrhoids.
As Google saves your location, that is why many ads are for businesses near you.
When it comes to GMail; well, http://www.youtube.com/watch?v=TDbrX5U75dk this says it all.
So you are being stalked, spied upon, and otherwise naked on main street.
However, there is another kind of Stalking in which one is followed from site to site by very very sick people. They may be your ‘Best Friend’ on Delphiforums, or Hubpages. They may appear to be a 31 year old mother of two, or a 27 year old geek. They may, in reality be a 61 year old embittered hag or a 58 year old pederest.
They may develope a pathological hatred for you to the extent they send Malware as gifts.
Unless you don’t use Google Search, have a number of email accounts on wierd servers, never use your real name and enter all sites by Proxy’s, you will be stalked. You can’t walk through a cow pasture without stepping in it.
Once you realise that you made a terrible mistake using your real name, posting an image, being too forthcoming on Facebook, you have to instantly correct the problem.
The first thing you do is create a new email account under another name, and have mail from bona fide friends directed there. You then close your previous email account.
You join all the sites you want to remain a member of in a different name, and close your accounts. If it is a writing site, download all your articles, (if you don’t have copies) then delete and close your old account. Everything that was posted has disappeared and you can repost on other writing sites without fear of plagiarism.
Once your stalker can’t find you, the stalking ends.
At least in Cyberspace.