There are tools that will track Amazon prices for you so you can grab a deal when the price is right, but why sign up for something when you can do it yourself with a simple Google document? This doc will track as many items as you want, and send you a daily digest of the prices and their changes.
Amit over at Digital Inspiration put this script together, and made the doc available to anyone to use. All you have to do is open the doc, make a new copy to your own Google Drive, select "Initialize" and then "Start Tracking" from the Price Tracker menu, and you're ready to go. Paste in the Amazon (every Amazon country URL is supported, along with Flipcart for those in India) product URL for the item you want to track. The sheet will update itself automatically, and you can paste in as many items as you like.
You'll get an email with the current prices of the products you want to track, and after that you'll get a daily email with the new prices, and an icon that shows you whether the price has gone up or down since the last update. That's all there is to it. You can't set specific price alerts obviously, and the digests are daily so you won't see a mid-day price drop that comes back up the next hour, but it's still a great way to keep an eye on something you've been budgeting for.
Hit the link here to go right to the sheet, or to visit Digital Inspiration to read more about it.
Create your own Price Tracker for Amazon and Flipkart using Google Docs | Digital Inspiration