Don't you know that you can Build Your Own Sports Car for as Little as £250 and Race It! ^price ^of ^the ^book ^not ^included
https://www.amazon.com/Build-Your-Sports-Little-%C2%A3250/dp/1859606369
That or any other LoCost building book will get you far.
You might not know anything now, but you sure as shit will by the time you're done. I recommend this - You don't have to even buy the book, all info is available online. https://locostusa.com/ is also a useful link. Legalities are something you need to check where you are. They vary from easy to "you can't do that". Find out first. Hint: Don't ask the DMV, ask local kit builders. They are motivated to help you make it happen. The DMV is motivated to "make you go away".
This is the one I built. Yes, it really is the wikipedia page one. It has long since been sold. The total cost was $7500 Canadian - about 6K USD at the time.
It's not that hard, but it is a lot of work. It's also totally worth it.
I dunno...
Maybe get busy with the welder!!
http://www.amazon.ca/Build-Your-Sports-Little-Pounds/dp/1859606369
You can also build a $30 thousand dollar Caterham sports car for $419 yourself.
Does that mean you should?