Can I download ldraw instructions from Lego Digital Designer?
Note that LEGO Digital Designer can also show you building steps, but the results have been known to be a little odd.

I'm not entirely sure what you're asking here:

Can I export models from LEGO Digital Designer as LDraw files?

Yes, although you will probably need to update the LDraw.xml file that LDD uses to export the parts. Once you've completed your model, chose File | Export and set the "Save as type" to (LDraw-Files (*.ldr)" you should then be able to open the file in MLCad, LEGO Instruction Creator or similar and generate your steps.

Where can I download simple LDD models from?

There is LEGO's own LEGO Digital Designer Gallery (currently being upgraded, so this is an archived instance) - each model has a "Download" link under it to download the .lxf. Other locations are probably available as well.