I've done plenty of projects using US Census Data.
I don't know what you mean by converting it? The census data is available for download in CSV, it's not like they are shipping it in some proprietary closed format which needs to be converted.
I'm still fairly new to Tableau so forgive me if I sound vague or uneducated. I've been using Aggdata for my Tableau projects and I'm a little unfamiliar with csv. So, it's easy to use census data in Tableau?
It's extremely straight forward to connect to csv. You may need to manipulate the structure of the data exported from the census website to suit your analysis requirements in Tableau though.
In my opinion Tableau doesn't make the process of using Census data any easier compared to any other data types. It definitely doesn't do anything specific for Census data to make that process easier. There's a bunch of built in background maps you can use which make it very easy to visualize a number of predetermined census metrics though - http://onlinehelp.tableau.com/current/pro/online/windows/en-us/help.htm#maps_mapsources.html%3FTocPath%3DMaps%7CBackgrou…
My post to your other question may help with this one. However, if you want to mention the census or ACS variables you need, the level of geography, and the area of the country, I can probably list the steps you would need to go through to get your data into Tableau. You will be getting into custom geocoding so be sure to read up and try that.