I live at 4 Crest Rd, Billerica, MA 01821-4307 USA. It's a block from the eastern shore of Nutting Lake, about five miles north of the Burlington Mall.
Google Maps gives some weird routes, so here's my driving advice: From I-95, take route 3 north to route 62 east, then make a left onto the Middlesex Turnpike. Turn right on Lexington Rd (at the 99 Restaurant), then left on Austin Rd (just past Schoolhouse Rd on the right). When Austin Rd ends, turn right onto Crest, and I'm the third house on the right. Park in front of my garage or in the lot to the right.
Public transportation: your best bet is to take the 350 bus from Alewife to the Burlington Mall. Alternatively, you can take the commuter rail (Lowell Line) from North Station to North Billerica. Either way, call me to pick you up (or call me ahead of time so I can meet you there). In theory, you could also take an LRTA bus (14 from the Burlington Mall, 13 from the North Billerica station), but those run hourly at best, and really it would be quicker for me to pick you up.
Feel free to email me or call me at (978) 362-3145 if you need any more information.