For mapping:
http://am190.no-ip.info
Original authors site from Advancemap.
Its the best map editor for Pokemon Advance series.
Also download elitemap because it has got lots of other hacking tools and scripting faqs+script patcher. The scripting program is called ScriptEd. With elitmap there are lots of other important tools, sprit editors and etc.
Havent used them for very long time, but I can tell you: If you spend well time on hacking pokemon games, you can achieve a lot out of it.
edit:
Also search for advance mart, advance text, advance point, Pokedex(only for german version) => all those tools are made by Scizz.
So search for those including the keyword "Scizz" and I am sure you will find them.
As I said, I dont do these stuff anymore, so I deleted every backup, and everything I had about pokemon hacking.
edit2: If you are totally newb to hacking pokemon games, you should read master doc from t3ch(or tech, or techzero cant remember).
His document(around 2003) helps starter out from beginning with all explanations. Sad that I havent got the file anmore.