http://webservices.amazon.com/onca/xml?Service=AWSECommerceService&AWSAccessKeyId=1XFK01HK9NZWGPENWGG2&Operation=ItemSearch&Version=2005-10-05&AssociateTag=&SearchIndex=DVD&ResponseGroup=Medium&MerchantId=Featured&Title=Star+Wars+Episode+3+-+Revenge+of+the+Sith
howto will help you create a simple method for your clients to add locative information to a travelogue. I've been fiddling with a lot of options for doing this, including using feeds with gmap macros.