Yes, google webmaster tools is an ideal tool to check that everything is working fine with the sitemap. I strongly recomend it. Apart it have invaluable statistic tools to better know the efficiency of your site.
I use the Sitemap Generator for wordpress by Arne Brachhold.. Works very well.. For the other sites, webmaster tools is pretty useful
I use sitemapspal.com for generating sitemaps.
i use google site map for my wordpress blog... its easy and done in second... you can have a try. if you have you website on wordpress. just open google and type "wordpress site map plugin"
Well, I posted three topics, under SEO and Search Engines topic. You can check how to make a robots.txt, sitemap and sitemap index files.
That may help =)