Is there a current way to access the AdWords API and get average monthly searches per keyword search?
Well, you need a MCC Google Adwords Account, then you need to singup to apply for Google Adwords API access, then Google team will review your request, etc., steps are listed inside their documentation. If they approve your request you will have free access until you reach an API limit treshold, from there on you have to pay. This is its rate sheet
Edit 1: There is a section called "Pricing and Compliance" on Google Adwords API FAQS
Edit 2: Google Adwords API limits:
Basic access: This is the default access level for all approved developer tokens. Basic access allows developers to execute up to 10,000 operations per day.
Why is the AdWords API being offered for free? We were charging a small fee for AdWords API usage to encourage developers to create applications that interact with the AdWords platform in an efficient and responsible manner. In 2010 we launched the preferred pricing program that offered free AdWords API units to eligible agencies and developers of search engine marketing (SEM) tools. We got positive feedback from this program and we now want to extend free usage to all developers to encourage innovation.