While doing an Internet search, I found that another site is using my company name. It is a construction company and is using the name for a construction product. I have a software development company. Is there a possible infringement on the name even though we are both using it for completely different purposes? I would like to avoid spending a lot of money on trademark searches if possible.
As a general rule, trademarks do not infringe one another if the underlying products or services of the two companies do not compete and are not distributed in the same trade channels.
As you describe your situation, you and the construction company are coexisting quite nicely. In other words, consumers of your business are not likely to be confused by the similarly named construction company. On that basis there is no infringement.
A moneysaving tip: You can search federally registered trademarks for free on the Internet at the USPTO website (www.uspto.gov).