What are the best growth hacking tactics for local businesses?

Hello, I myself do not have much hands on experience with growth hacking , but I can offer some thoughts on the subject.
I'm not quite sure what you're looking for in terms of your question though? Are you looking for ideas or methods for growth using the growth hacker mentality for local brick and mortar businesses? Are you looking to bring these brick and mortar businesses online and increasing their lead captures?

If I were to take a local photography service and try to increase growth in a local area there would be a couple of things I would focus on when it comes to growth hacking.
The first thing I would look at is the actual product that is being offered. Then I would see if I could use the product itself to increase growth for itself. Make sense? What is the product of the photographer? I would think that the product would be the photos produced. So I would then figure out how I could use the photos to increase the photo shoots done with my photography studio. One way to do this may be to offer some sort of deal to people that share the photos on social media and get their friends and family to sign up. If I were the photographer I would tell my customers that if their friends and family like and comment on my Facebook page about their photos I would give their friends and family a free 8x10 photo on their first shoot. If 10 of their friends sign up for a shoot I would then give my original customer some sort of thank you in the form of free prints or something similar that makes sense for the business. Use the product to market itself.

Another thing I would be looking at is the distribution of my product. In the local scene I feel that online directories, live events, local media, and forming business partnerships are critical. If I were a local photographer I would be at as many local events as possible taking photos. I would then place these photos online where they could be viewed and purchased.

I do offer consulting in the area of local marketing and would love to chat with you in more detail about what you are looking to achieve. Schedule a time to talk. I'm sure we can come up with some great actionable ideas that can help with lead generation.

A simple tactic and shortcut is to use your personal network. Lots of people miss the fact that they have a huge number of personal and business contacts (look at your mobile phone contact list). Engage them, tell them what you do and specifically who you are looking for (local photographers). You will be surprised with how well your network can support your business growth.
NOTE - if you haven't got a lot of contacts on your phone, sit down with a sheet of paper and a pen and list everyone you know (business and personal). We often forget how many people we have met over the years.

1. Be Google enabled, - make sure you have listings on all the local directory sites (Yellow Pages plus others).
2. Subscribe to local newsletters who circulate 'what to do' listings each week - get your products and services onto these mailing lists
3. Get individual businesses to cross-sell each other to their own lists. Low cost and gains reach fast

Some good options include exit popups, lightbox overlays and squeeze pages.

According to Conversion Sciences, correct implementation of exit popups can reduce the amount of visitors who leave your site without taking action by anywhere from 10-15%. These popups are triggered when a visitor moves their mouse near the “back” button or toward the “X” to close out a window – or when they haven’t moved their mouse for a certain amount of time.

Lightbox overlays are similar to exit popups in that they appear on top of the content of the actual page a visitor is on – but they aren’t necessarily triggered during exit-intent actions. A good way to think about it is: exit popups are a type of lightbox overlay.

Finally, squeeze pages may include offers for further information or freebies, such as ebooks, customer testimonials, and how-to videos – but would require the visitor to enter their email address or other contact information before providing access to such content. In turn, not only will the visitor receive the content they requested, but they’ve also opened the door for the company to send further information in the future.

You can find more info on all of these — and how to grow your local business using them — in Fieldboom's blog: http://www.fieldboom.com/blog/growth-hacking-exit-popups-lightbox-overlays-squeeze-pages-leads/.