Send you ad traffic to a unique form per campaign so you know what campaign is generating leads.
This isn't rocket science.
Also, Google Adwords counts conversions for visits for 30 days. Which means on the 1st visit from the ad campaign, there can be no immediate conversion (and that's OK). But if the same person returns to the website (not from the ad) and downloads/signs up that would be counted as conversion attributed to the ad.
Track hits on a post-download URL
> signups
Count signups in your DB with a source from a hidden field on the form
> Also, Google Adwords counts conversions for visits for 30 days
This stuff is mostly meaningless.
It will be mixed with downloads that come from organic search.
>This stuff is mostly meaningless.
I disagree.
Use a different page/form to track the two separately.