automatic 3 speed shift kit???

I see people with the auto 3 speed th350's for drag racing.  They have some kind of shift kit?  Is this normal and what is it all about?
I have a 3 speed auto and if I can set it up for racing without replacing the tranny that would be nice.
Any info is appreciated.
THanks
b

Check out Summit and Jegs.  They both sell multiple shift kits ("slap shifters") for the TH350.

bill.

Thanks, went to both sites.  What exactly am I looking for.  I did a search for shift kits and th350 and I'm just not sure what I'm getting.  Also, is this something a professional should do for me when I decide to do it.  I have never worked on a tranny before, typically I don't mess with trannies.