When I used to lookup my ip using the ip address lookup tool, it used to show a location almost exactly where I live. Now, it just shows the city (I don't live near the city centre). I don't think my ip has changed since the earlier lookup. Is there some other explanation as to this loss of precision? Has my ISP blocked that info or has the lookup procedure changed or something else? Thanks.
The information you get from "IP Lookup Tools" is simply relayed information from one of the international databases that control the distribution of IP addresses. If you were in the US it would come from the ARIN database. In Australia it would come from the APNIC database. The exact result you get will vary somewhat in different lookup tools depending on how their configured.
Did you use the same lookup tool both times? If you did, it's possible the data was updated between the first and second lookups.
I looked up your IP and came up with two different cities from two different lookup tools.