I am also a big fan of including regions in the domain name. Also to include other keywords. Google values both quite highly. I'd advise that your main domain be something like www.mslawncut.com. I also suggest you purchase www.smithlawnservice.net. That would have an autodirect to your primary domain. This will cover you in case someone does a search on "Smith Lawn Service". The autodirect won't rank in Google, but Google probably will recognize the redirect when the exact name is entered. Another thought, if you go with mslawncut.com (or similar), you might want to file a DBA (doing business as) for that name (include the .com) attached to your business.