|Official site of Andrew Doull|
I'm currently the maintainer for UnAngband, which has been in active development since 1997. I lost the code to an earlier version of UnAngband which also featured terrain which I had been working on since about 1993. So that's a long development time all up, with no sign soon of reaching version 1.0.
My favourite roguelike is the Angband variant SAngband and I've learnt a lot from Leon Marrick and Eytan Zweig, developer of EyAngband about coding roguelikes, by reading the source code for the above games. I highly recommend that you consider trying to modify an existing roguelike game, like Angband instead of trying to develop your own roguelike from scratch. If you have an aversion to C then consider ToME which supports most of the code in Lua, a light-weight scriptable language.
Of course, what I really want to do is re-write LAngband. I'm also secretly working on a game, tentatively titled Millenium, which will be based on roguelike development principles, but using a 3D engine set in the modern world. For inspiration for this game, you might want to look at the Introversion blog and Infinity: The Quest for Earth. Of course, that won't help you much at this stage.
For my latest thoughts regarding roguelikes and gaming in general, read Ascii Dreams.