If you want to make the background a perfect white before photoshop you need to light it with separate lights, with grids so the light will only hit the background and not the product...turning up the lights will overexpose the background turning to a perfect white and no post editing. The background has to be far enough away that it doesn't reflect a bunch of light back at the product, and from my experience doesn't work well with glass.
The plexiglass technique chip mentioned works great
on smaller stuff.
I have the Scott Kelby channels book and it has some great tips on complex selections, the masking book by Katrin Eismann i've heard is great and is on my list to buy soon.
A great free resource for lighting products http://www.photoflexlightingschool.c...ife/index.html