Here is a list of the free 3d moddellers i know of which let you save files in a format DB can use:
Anim8or - www.anim8or.com
lets you save as 3ds files which can be converted.
you can do animation too...but i've never done that
Metasequoia - http://www1.sphere.ne.jp/mizno/main_e.html
got to be one of the best - can save files as *.x as well as many other formats.
Doga - http://www.doga.co.jp/english/index.html
there are 3 different programs L1,L2,L3 they get better as they go along. L1 is completely free and very easy to use - has about 500 preset 'parts' which can be positioned,rotated etc. L2 and L3 need to be registered.The feature "Render / View animations" is not available till you register, but that is OK for me as I don't do animations. all the programs support *.x file exports. you can't texture objects made in Doga L1 though
3d designer - http://www.3d-designer.com/index.html
this is a cool program but i have not downloaded it and tried it out. exports .3ds and .x files. shareware restriction means it puts a watermark in objects created though.
There are many more 3d designers but i won't list them all here
Hope this helps
Robin
http://http://www.thedbzone.on.to