Like so many have said, Stihl does not discount saws very much and dealers are forbidden to sell over the internet under their business plan. You might get a few bucks off at a dealer wanting to move merchandise and maybe a extra chain or oil, but that's about it. I've bought 3 new Stihl chainsaws in my life and one brush cutter and the most I got off sticker was $25 plus a B&C upgrade
My advice? Dump the Stihl idea all together and start shopping Husqvarna online and at the dealer. Stihl makes mediocre, middling and pro saws. Their pro saws aren't junk and they are reliable, but in every power category and in every conceivable application, there's a better Husky pro alternative. Stihl spends oodles of money every year in advertising to make you think they make the best saws on the planet and guess what? It works well for the uninformed. JMHO from a former Stihl junkie who saw the light and now purchases Husqvarna pro equipment.
If you're looking at cheaper (less capable) consumer grade saws, I'd skip Stihl and Husqvarna altogether and look at Echo. They make decent saws with better filtration and a bit better construction than the bottom feeders from Stihl and Husky. Buy from a dealer and not from big box store. If you can work on your own equipment and don't mind not having a dealer close by (this varies obviously), look at Dolmar. Pro grade construction at consumer grade pricing. They tend to be a little heavier than the competition if that matters though.