I emailed the dealers in our area for estimates, then went to the one that offered the best price (he also delivers for free - not bad, since we live about 50 miles away. The other dealer - who is closer to us - doesn't deliver).
When we went in to the dealer last week, I didn't mention the estimate - wanted to see what he would tell us (this guy was different from the one that sent us the quote). I wasn't prepared to dicker with him, but he heard me debating with my husband about the value of a particular feature (B7510DT versus B7510DTN). Wanting the sale of the DTN, he brought the price down on it, also cut the cost of the brush hog. Still not as good as the price of the estimate, so I told him that we'd been offered less. He saw the email - and we get it for that price.
My only mistake was in appearing too eager - when we walked in there, he knew that we'd done research about models, etc., so he didn't have a difficult time selling us on that tractor.
It doesn't hurt to try for a lower price, or to get the dealer to throw in something extra. If you don't get the better price, at least you tried!