Can I locate my android phone? I brought a new Samsung Galaxy Y inbuilt with Android 2.3.5 some month ago and sold it recently. But after selling I noticed that in that Android I left my email ID (email ID that is used to log in to android for the first time).

I don't worry about the my email ID as I have changed its password but Can I locate my android device with that email? or by any other way? on any Google Maps like service?
No, you would need an application like "Where's My Droid" installed on the device and know the phone number for the device. 

If you sold the device, the new owner probably did a factory reset on the device so your information is no longer associated to the device. 

In the future, before you sell your device, you should go in and do a factory reset so you are not giving the device away with any of your information. 

I want to add my opinion on these apps that claim to help you find your device (including "Where's My Droid") if it is lost or stolen. They are great if you lost your phone in your house (or somewhere "safe") but if you lost it at like a bar or if someone actually stole it, chances are you will not even be able to use this software. A factory reset can be done on any device rather quickly, which would remove your "locating software" and remove any "tie" that your accounts may have to the device. Also, they require the device be ON, so if someone does steal your phone, all they have to do is turn it off, and when they have a chance, do a factory reset. My best advice I can give you is to remember that these are ~$600 devices (what you will pay off contract, or for a replacement) so treat it like it is a ~$600 device and don't leave it laying around. I am not saying that I would ever take someones phone or anything, but I could have the device factory reset by the time I got to the door to leave. It is as easy as Menu -> Settings -> Privacy -> Factory Data Reset.