Is creating an XML sitemap for submissions to major search engines a simple task? Or is it something you need to purchase from a company or software application>
Thanks
after doing once its really a simple task
Its an advantage to have a Sitemap in your site or blog, SE will easily determine the content and crawled it regularly, its a neat and clean way of crawling and getting index of your site.
btw… some search engines have a different format for sitemap… like google xml and for yahoo i think is txt file…
Another Designer: Check the following website which has the sitemap specification, it’s got less elements than HTML to remember and requires less work to create it, you can create whatever you need by hand with little effort - clean, simple and no applications required. http://sitemaps.org/protocol.php
If you think that Jeff, you’re doing it wrong. The Sitemap specification is 1,000 times easier than learning HTML. 
Once my website became relatvely stable a few years ago I used sitemapNG to crawl my site and create the sitemap.xml file. Since then it’s a simple matter of hand-coding in/out any of the very rare new/removed pages.
For my WordPress blog I use the Sitemap Generator plugin. After making a few config settings it takes care of itself, even makes a compressed version.
I’ve never used it, but AFAIK Google has a sitemap generator tool or three.
You may need a “Webmaster” account to use it, but IMHO if you don’t have an account already you should get one anyway if not for the sitemap tool for the SEO tools.
Doing it by hand isn’t a simple task given the nature of the file. That being said, there are a variety of ways to have a sitemap created for you for free or very low cost.
If your website is driven by a content management system such as WordPress, it’s either already done automatically for you or can be accomplished with a plugin.
If you’re not using a CMS, my favorite generator is: http://www.xml-sitemaps.com. It’s free up to (I think) 500 pages. After that, it’s a very low cost for a great service.
Last I knew Yahoo now reads both formats. In fact it’s been a while since I saw the text file format and I’d be a bit surprized if they hadn’t deprecated it yet.
AFAIK the Google XML format is the de facto standard now.