Using Google's Advanced Search

If you want to find something, and just using simple terms isn't getting you there, you should try Google's advanced search There's a graphical interface, but to be really productive, learn the text commands you can type inside the normal search box. Commands are a word followed by a ':' character, with no space before the colon, followed immediately by the setting for the command, for example:
site:petewarden.typepad.com google

1. Site. This is the operator I use the most, because Google is better than most site's built-in search. I'll often pick a documentation base address and use it like site:msdn.microsoft.com xml. One lesser-known use is restricting your search to a country or other domain, all you have to do is put the top-level domain after the site operator. Here's how you'd search for pages on opticl flow from only US education sites; site:edu optical flow.
2. Cache. If you put a web-page address after this, you'll see the version of the page that Google picked up when it last indexed the site. It's the same view you see below the main link as "Cache" in the search results, and is very handy for sites that are temporarily down. They may still try to load images or other elements that stall page loading, so if you want to see just the text, add &strip=1 to the end of the Google search URL.
3. Link. This is so nearly so cool. It's supposed to show all pages that link to a certain page. In practice, it shows some, but not all, and there's speculation that's because showing them all would give too much information about Google's database. It's still useful if you've got a page you like, and want to find others in the same area, just don't expect it to show all links.
4. Synonyms-'~'. Putting the tilde character, '~', in front of a word will expand the search to include words that google thinks mean the same thing. Google does this automatically in a lot of cases now, and it only works for common words, for example trying ~trainers (which is a British way of saying sneakers) doesn't bring up alternate shoe sites, unlike ~sneakers, which is recognized.
5. Filetype. This lets you restrict your search to addresses that end with the extension you specify. Google can only understand thirteen types of files though, so doing a search for filetype:mp3 won't give you any music results!
6. Exclude-'-'. The minus sign, '-', in front of a search word, means don't show any pages that include that word. This is really useful if you're getting a lot of results that are from an area you're not interested in, you can pick a term that's common to that area, and hopefully most of those pages will contain it, and they'll disappear from your results. For example, if you were looking for gateway computers, but meant the network technical term rather than the company, you could add -buy -inc to exclude a lot of the commercial pages, and find the ones you want more easily.
7. Or-'|'. Using the vertical bar symbol, '|', between two terms, will find pages that contain either of the terms. This is mostly useful if you're getting too few results and want to expand your search to similar words.
8. Wildcard-'*'. This is only useful as part of a quoted search, where you're looking for an exact phrase, but there's a section you don't know. For example "senator * spoke against the war" will find all the pages that mention particular senators.
9. Related. This will find any pages that are similar to the URL you enter, using Google's criteria for similarity. It can sometimes be useful if you want to get more search results based on one good page you've found.
10. Intitle. If you're getting too many results, and you really want to restrict them to just those with a given word in the title, this allows you to limit your search to just those.

For a really good in-depth guide to searching with Google, I highly recommend http://www.googleguide.com, it contains really detailed tutorials to improve your searching.

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