LOL, this thread just cracked me up - sorry, but I just had to get that out.
If you're looking to alter things in the game, I'd start by editing the .ufo files, which on Windows can be altered with a standard text editor (such as notepad, no hex editor required). I think that would be a much easier approach with a lot less work - those .ufo files allow changes to just about everything (how much money you start with, weapon stats and firemodes, base facility capacity, etc., etc.).
I think I see where you're coming from though, if you're rather new to the project - I remember days when I would look for editors for a lot of commercial games, and try to alter things myself, sometimes with hex editors. This project is a bit different, it's open-source, anyone can alter the source code if they know how to program in C, and if they aren't a programmer they can still do quite a bit with the .ufo files to re-work the game. The whole project is fairly open, there's really no need to try to "hack" it.
If you're running windows and want to change things in-game, or outright "cheat," you might also look into a program called GameWiz32 (Google it and you'll get download links from various places). It's creator no longer has his website up, but it's still on a lot of download servers out there, and it is very quick and easy to use (no programming knowledge required, it alters memory while the game is running to give you more money, freeze health or ammunition while playing, etc.) Please note before you grab it though, that I don't know if it's completely clean or not. Download.com and other such sites say it is clean, but I've known for them to occasionally miss some adware-type stuff. I will say that I tried it a long time ago and never had any issues from it, and it works with almost any game.