Trademark My LLC just received a C&D for operating website with same name

[RoundBlock]

I own a Nevada LLC which operates community websites. One of our sites has been operating since April, 2011, first under me personally, then by the corp after I setup the LLC. We'll call the domain name "southwesthotrods.com".

An Arizona company by the name of "Arizona Hotrods, Inc" just sent me a C&D letter, stating I'll be facing legal action for using the name "Arizona Hotrods", and Arizona Trade Name. It appears they incorporated in February, 2011. I did not find a record of a trademark in the TESS lookup.

How does this play out? What can I do to avoid this in the future, with other websites of ours?

 

[RoundBlock]

I made a mistake in the example, it should have read Southwest Hotrods rather than Arizona Hotrods. We're using southwesthotrods.com and they're Southwest Hotrods Inc.

Also wanted to note, they build and sell hotrods, we run a website for hotrod enthusiasts of the Southwest. We have no physical presence in Arizona, and we're incorporated in Nevada.