I'm following a big community of watch lovers & enthusiasts on Instagram, Tumblr & Pinterest. Google Shopping Campaigns is indeed a great way to generate traffic from bottom-of-funnel customers that know exactly what they want and they are simply shopping for the best price. If you want to raise awareness of your site by focusing on middle-of-the-funnel customers that are looking for watch retails, Google Adwords will be best but keep in mind, it will cost you money since shoppers are not sure exactly what they want.
Targeting Top-of-the-funnel customers is harder and takes longer but doesn't require much investment if you know how to create interesting content and publish it all over the internet by focusing on Social Media. Get involved in the watch community across all social platforms and raise your voice. Show them how passionate you are about your product and how knowledgeable you are about the industry. Create curiosity and they will start poking. Show your art on visual networks such as Instagram/Pinterest/Flikr/Tumblr.

Read amazing posts on http://blog.Hubpot.com about inbound marketing!

Good luck!