Is there a "go-to" resource, magazine or website that restaurant owners use to buy equipment, and get advice?

I think FB & LinkedIn would be 2 great places.  I've seen FB ads that suggest finding any group you'd like to connect to. I'm sure pretty much all restaurants are on FB & LinkedIn. You can also place ads to targeted audiences on FB as well. All the best to you! Aloha~~

depends on what you need.  What kind of a restaurant ? Webstaurant is decent site. 

depending on your area, I would use local flyers to business and drop them of at places that will let you leave some So there customers can take them as well. Also you can do those mass mailings to everyone if you offer coupons and things as well, small radio ads. See what local newspaper or magazine in the area Facebook and any of the social media. If you have any fairs or things like that get involved with the community so your business stands out. Don’t limit yourself to just one way to get your name out there plus you have this site to help with advice and there are others like this if you research.

Check out The Restaurant Boss. Some of his advice is pretty good. 

Nations Restaurant News

webstaurant  it’s on the web they carry all restaurant needs 

For lighting, look for the NSF Certification.  The CGE LED UFO High Bay Light is an eco-friendly solution to illuminating large food processing facilities. Applications include restaurant kitchens, food distribution warehouses, and food processing or production. They provide illumination between 20ft - 40ft. The UFO High Bay LED Lights do not contain mercury, or emit IR or UV radiation. 

what services do you want to sell them?  (this helps identify better options) for example, without knowing, anyone could say google. so there- google - popular directory, facebook, instagram, twitter, there's a few. 

if you're willing to be a bit more specific, I can help you dive into a pool of places you just may appreciated. 

Be Encouraged, 
          Andrew

Restaurant owner.com

Every state has a restaurant association. I would start there. Starting on a national basis could be more than you want to bite off in the beginning.