It's quite common for people DIY loudspeakers to use automotive paint on wood. See here for example:
http://www.diyaudio.com/forums/showt...threadid=83141
Although the material used is usually MDF not real wood. If you are using real wood you would need to take a few extra steps to avoid the wood grain showing through the paint
If I were to paint an ikea wooden dorr I would have done the following to prepare the door before painting it.
1. Sand away the laquer of the door
2. Use some kind pore filler
3. Sand it flat
A rule of thumb here is that any uneveness you can feel with you're fingers will show up through the paint.
Frode