Hi! I'd recommend using a range of venues to get the word out about your expansion, in addition to web-based vehicles (which are great!). Train station platform advertising can be a terrifc way to announce your expansion, for much less that the cost of decent size print ad in your daily paper and thousands of eyes see it every day ( would suggest a min. of a 2 month campaign to get great brand / expansion exposure).

I'd also suggest your firm join the major Chambers of Commerce in those two counties, and do a very targeted mailing to their members ( perhaps as an add-in mailing to their regular newsletters??) Don't just do a flyer (you want to stand out, right?). Instead send an oversized postcard that is professionally designed and written, perhaps with a flap that opens.

Share the news with all your current clients, as you never know who they know. Send them a formal announcement ( again professionally designed) announcing your expansion.

Best of luck with everything!