Can you share your experience or advice about buyer research? I'm thinking of what you could learn from decision makers before they've become customers.

Such a wonderful question. I'm a big proponent of doing this. First, identify your target market and job titles of your target buyer. Then interview them to get a good understanding of the problems they face, uses cases they may have, and how they search for solutions. Your goal is to get a robust perspective of the market problems, potential competition in the space, and what your buyer cares about in order to create a differentiated, value-driven experience.

This one’s a sensitive one, since it’s tough (and not necessarily good for the business) to get in the middle of a sales process.  I’ve found most success reaching out to folks cold who are not in a buying cycle, and currently use a competitor, with the offer of just trying to learn more about their needs.  Even better if you have direct collaboration with Product and can tell the interviewees that what you learn from them will influence the solution you’re building, which would be available to them when their contract’s up.  If you think there’s a lot of value in talking to folks that are close to their sales cycles, I’ve found it really helpful to bring in a third party so they can aggregate information, so that you’re not viewed (internally or externally) as manipulating the sales process.

Buyer research comes in two forms - existing customers and prospects. 

Tap into your existing customers to learn what really sticked during the sales cycle and what their 'aha' moment was in the product. The key is to find the PAIN they were in before this product. 

Then, do some networking on LinkedIn. I usually will offer free coffee or some kind of incentive and ask for feedback on messaging for a product. These folks really have nothing to lose, so they'll be upfront with any hesitations they have!