We all have our tips and tricks for troubleshooting. I certainly have a little bag full of fun toys that I can use to figure out what's going on when something isn't behaving correctly.
One of the tools I found was DNS Report. This site will take a DNS name, resolve it and check potential things that could go wrong with a domain name. Although this is a good site to use if you want to make sure you're setup correctly.
Microsoft provides another tool called DNSLint. This tool is a windows utility that outputs an HTML file to help you diagnose common DNS name resolution issues.
With both of these tools under your belt, you're setup for a successful DNS setup!