These are a variety of links that will be helpful for people who are interested in promoting their websites online:
Register Additional Domain Names: It is helpful to "protect" your domain name by registering the .com, .net, .org versions of the name. It is also helpful to register common misspellings of your name. And if your name is not available, remember to check the .biz, .us, .info, .cc versions of your name also.
Search Engine Data Sources: Where do the search engines get their information from? A lot of it they get from each other. Check this link for a good overview of who-gets-what-from-whom. You will be surprised to learn how many of them get their information from the same places.
Who Is Report: Trying to come up with the right domain name? Curious about who owns one? This is a very useful site for helping you to find the right name and for doing lots of research about domain names.
Name Droppers: Another site that will allow you to put in any string of characters and see all of the domain names that contain that string. Great to find out who may be crowding your chosen name. It also provides a convenient lookup so you can find out who they are.
Deleted Domains: Every day there are thousands of domain names that are not renewed. You can use this list to identify domain names that have expired and/or are in the process of being dropped.
Link Popularity: Want a quick way to determine how popular your website is? Or one of your competitors? This useful site lets you identify the links held by your competitors (and, after all, if they are giving a link to your competitor, why wouldn't they give one to you too?). And, don't forget that increasing the number of other websites that have links to yours is a very important strategy for getting placed higher in the search engines.
NetMechanic: This site will help you review any single page on your site (be sure to do your main page at least) for broken links, HTML coding, browser compatability, load time, and spelling.
The Anonymizer: This site is useful when you want to see your website "from the outside". It uses an anonymous proxy server to view your webpage. If you are hearing about problems on your site, go here to view your site. The reason this is helpful, is that sometimes when you publish your site, there will be links that appear to you to be working because they are linked to your C: drive. They are not going to work for anyone else, however.
Search Engine News: This is a great site for learning all the ins and outs of search engine optimization.
Cool Home Pages: Looking for new ideas to spice up your website? Check out this site.