Value of VDP #1: Relevance.
It might be difficult for some of your customers to imagine personalized campaigns for themselves and their products if they don't currently use it. (unless you cater to large companies and your customer/orderer is a direct marketing expert). Allowing them to see ideas of what is being done by others in the same industry (travel, banking, real estate, etc) is the best way to get some ideas flowing in their minds. Aim at segmenting your database per industry type, and give it a try. In order to convince on the value, putting your hands on a few case studies and stats that are industry specific can also be shared with them. The map idea is also good, but watch out for birdseye view (radius) distance versus road distance to your store, especially if you are in an area with rivers, or any natural obstacles of such.
Value of VDP #2: Accuracy.
Before you get started, make sure your data is clean. There is no such irritation for some of your customers as to receive something like : Mr. Jane Doe or MISS JANE DOÉ, etc... The extra time you spend on making your data clean, the higher the results.
Value of VDP #3: It's a relationship.
Since you are communicating one-to-one, address your customers and your prospects differently. it's like a relationship, depending on your level of intimacy, you might address someone differently. Invite them to engage with you and use a one on one tone to your content. Also plan ahead what concrete action the customer should take, and insure it is out loud and clear on your piece. If you really want to get into it, I would also suggest planning step 2 ahead of time... what happens after your first mailing. A call, another mailing etc. Building a logical sequence can most definitely impact results also.
Hope this is helpful.
Julie