Nocturnal,

I’m not really sure if you are spending too much or not because I don’t know what your keywords are however I can tell you how to make a good estimate.

You can look at average CPC in the Google Keyword tool to gauge how much you should be spending. You can also try manipulating your max bid per keyword (moving it lower) and see if it negatively impacts your other metrics.

Here is a post on top-page bids,

Top of page bid estimates - Inside AdWords

Here is another one on how to set your budget,

How to Set Your AdWords Budget: New Shared AdWords Budget Options | WordStream

Hope that helps,

Shawn

Only you can gauge if you're spending too much. You need to determine how much you make per lead/optin, then you need to make sure your Cost/Conv. don't exceed that.

If you're at a reletively high Avg.Pos. bidding at $0.60, then you can always try and lower your bids and see if you can still get the desired amount of traffic. If your campaign is "limited by budget", then lower your bids by small increments until you're hitting your daily budget but are no longer limited. This makes sure you're not bidding more than you need to be.

The best idea is spend money to test some products, and know which product is giving you earning then stick with that.