Well first off I'd like to start by saying I've been lurking these forums for quite awhile now, absorbing as much knowledge as I can. I've really learned much from both Ascension and pasis in particular so extra thanks go to them for helping me with their tutorials.
I started with this map because I'm writing a novel and figured I should design the world first and then work my way up from there because our surroundings really define our culture. Trying to determine how the people of this fantasy land would react and adapt to their surroundings actually helped me come up with quite a few new ideas just from drawing the map. I've even done the constellations and zodiac but that's for another forum probably, haha.
But basically I started this map off sometime last year with a basic idea of what I wanted. I tried out many different programs and couldn't afford others but I came upon this great game that comes in to play with how my map was designed. Some of you may have played it, it's called Dwarf Fortress and it's really quite amazing beyond the first look at its gameplay. It has so much depth below the surface.
One interesting area for map makers is the fact that it can randomly generate worlds and it fills it full of biomes, lakes and mountains, even throwing in some fantasy elements like holy and evil lands, even zombie oceans! It isn't perfect by any means but when you look at the basic topographic map I provided below you will see it really does a great job of making sense in terms of rivers, elevations and gives some nice land layouts.
The scale is roughly the size of England at the largest map size or so I've heard so that gives you an idea of what you could create, so beyond that it might be not as realistic as you hope.
A bit of warning for those trying out the program to develop maps through DF is that you have to play around with the settings until you can get continent shaped areas as the default map generator tends to create large landmasses with no oceans. I really enjoyed using it however and the fact that it gives you all the biomes you need, temperatures, rainfall etc. makes it really unique.
Anyways, for the map I made I did everything with a mouse, did it in Photoshop and took me about a month to finish this version of the map as I've started from scratch six or seven times from last year to now determining what style I wanted to use for the map.
But without further ado here is the finished result: