Problem: You need to know how many people visited a website after finding it on a flyer or some other physical artifact.
One Solution: Tailored Landing Pages
A landing page is a special page you add to your website meant for a specific audience. This page could mirror your home page, provide specific information tailored for the audience, or just redirect to your normal home page. Landing pages are as cheap as any other page on your website.
So how does this solve your problem? Your landing page has a unique URL that only those reading your flyer will see. So any visits to that link, recorded through analytics, can be attributed to that specific audience. If it’s important enough, you could even consider purchasing a new web address specifically for the landing page (less than $20/year).
Now if you don’t have the ability to create a landing page you are not out of luck. Just plug your regular link into a link shortener site like Bit.ly then put that link on your flyer. The analytics might not be as good as Google’s but it’s quick and easy.