I run the site http://www.ballofdirt.com with a couple of friends - the maps for each travel journal, e.g.
http://www.ballofdirt.com/journeys/6653.html

We want to put OSM in as a layer on the maps - can you help?

The current maps are done using our own software that takes digital elevation data and plots the colours accordingly (with a bit of shadow).

We have made it turn into Mercator projection and just need to turn the maps into tile numbers, so that they fit under the OSM maps. I think we might need to create our own tile server (??) and pull updates from OSM as well. Can you help advise and code?