You can tune more with a carb without needing to burn chips etc..that makes it worth it to some people right there. I'm still enjoying the challenge of tuning the F.I. though (still running the factory computer with no chip). If I was to build a race only car it would definitly be carbed, but the EFI is more street friendly IMO.
Just buy any carb tuning book at Borders and you'll probably learn everything there is to know about it. The fact that (i dont think..) you can even buy a carbed car anymore means that we've pretty much learned all there is to learn about'em.
Carburetors are a cinch and if you know what you are doing then they will get the same mileage as EFI. I just took a 150 mile roadtrip in my 516 rwhp carbed 85 and it got 15 mpg. A new carb out of the box is wet tested and will get your car running just fine. It may take a few jet changes on a dyno to dial things in but thats it.