The HPI E10 is designed as a very entry level car that can be used to bash in the street or drift. You can make a E10 race worthy, but as others have pointed out that can be expensive.
The best option for a new racer with a limited budget is to buy a good used touring car that still has lots of part support. I would suggest if you have a local track/hobby shop, that you should find out what is raced locally. Many racers have an opinion on what the best car is, but good local support can be worth a lot when starting out new.
I'm currently racing VTA. Check here for rules/info: http://www.usvintagetransam.com/