As mentioned before, you first have to think about, what you wanna do. Me for example started modeling few months ago, just to see how it works. At the moment I am modeling a weapon and trying to texture it. And the fears you have about not having any experience are not relevant, as everybody has started anything from scratch. Nobody of the Devs was born with the possibilties for modding. They all decided to learn it from scratch and as you can see, they did it very well
So if you want to model something you have to get 3ds max 9 ( there are also more up-to-date versions, but the v.9 is the last one, that supports the battlefield 2 plugin. For texturing you can use Adobe Photoshop CS5 (it is the newest version, I think). - The only problem with this Programs: they cost money and are quiet expensive. But you can try to get a trial version of them just to see alittlebit how it works and to see, whether it makes fun. To my mind modeling and texturing are very nice, kind of meditative.
Good tutorials are described in the modding section. There is a very good tutorial about modeling a Beretta 9000 in the thread "How to model a handweopon". There are a lot lot of basics explained. Another good tutorial is this one, as it shows you, how to unwrap step by step and how to use photoshop:
http://www.moddb.com/tutorials/creating-a-weapon-for-source-part-2 But don't make the mistake as me and start modeling a rifle - it can get very painful but it is also a big challenge and when stay on it you get a lot of techniques. For example how to texture a scope lense or a wooden texture (what is still a big problem for me). I think it is better, if you start with a knife or a pistol.
You can also try to do mapping, what is more needed for the mod, as I got it right from the statements of the devs. Good thing is: you only need the BF2editor, what is free and some other stuff (object.zips) and so on. You can find this files also in the modding section. There are also a lot of turorials in the www. in this case google is your friend.
So I hope this helps you a littlebit.