General Tips
- Use a variety of search engines - depending on the topic each search engine will return different results. Try entering your keywords into a few search engines and evaluate their results.

- Vary your keywords - If a search engine is not returning useful results, try being more specific or adding a detail. You also may want to try searching for a parallel or conceptually similar phrase which may turn up pertinant information.

- Bookmark everything - There's nothing worse than spending an hour browsing, and realizing the site you were at 40 minutes ago was the site you wanted! If a page has some decent content, bookmark it. You can always clean up the bookmarks later.

Links
CBB Recommended Web Search Sites - Colby, Bates and Bowdoin jointly developed this site detailing different catagories of search engines and giving useful information about the best ones.

Search Engine Watch - A site dedicated to providing in depth information about search engine technology, user tips and news.

Search IQ - ZDnet's site dedicated to information about search engines including user reviews, news and tutorial links.