Installers don't like to talk about the cost of the panels, since your installation cost is so much more. That doesn't mean that installers are getting rich - it just means that workers' comp and permits and sitting around waiting for the inspector and all the other costs quickly add up.
One easy way to learn what panels cost is to search on eBay, under completed sales. That way you have a price point for single panels and for pallets of panels. But your installer may well be paying more for his panels, since he/she is depending on the guarantees that often don't accompany gray market items on eBay.
As an aside, your inquiry asked for a price per watt
. Note that installations can be sized in STC watts, PTC watts, AC watts, etc. Here's my attempt at an explanation: Understanding the marketing sheets
Now's a very good time to buy panels, as the market is flooded. But your local installer may not want to deal with panels you supply. And if he IS willing to install them, he might just recapture the lost profit by padding his installation charge.