Well I'm not sure about Darkbasic personally, but if it's similar to FPSC then it's quite simple in fact. If say, you've downloaded some free media produced by a generous forum member, all you have to do is put it in the right folder:
Let's just say for example you went into
Kravenwolf's free media thread and downloaded his new shopping cart. Once it's downloaded, you unzip the file (I suggest
Winzip if you don't already have it). Then, you'll see within the folder you've extracted, the components of the model (texture, FPE file etc.), and all you have to do is place these in your
entitybank folder, mine as I'm sure most are, can be located at:
Local Disk C: -> Program Files -> The Game Creators -> FPS Creator -> Files -> Entitybank
I hope this helped. If this wasn't at all what you were asking then I'm sorry. If you're question was geared towards how
you could personally make media to put into FPSC, then that's a very different story obviously.
I'm not a modeller, but if you're looking for an idea of where to start program-wise, you might want to take a look
here. As for tutorials for getting guns into FPSC precisely, I'm sure you can find some tutorials around the forums based on what program you're using.
This would be a great start if you chose
Blender.
If you've got anymore questions, I can't really help in the actual process of getting media "FPSC ready", but I can always try and point you in the right direction.
Good luck man!
Cheers
Life would be much easier if I had the source code.