12's is not fast. too many cars are there nowadays. an ls1 camaro is hard to get fast and still be reliable for dd. unless you nickel and dime everything, do the installs, and nothing breaks.
to get into the 12's is easy with nitrous. you could get a wet kit for ~6-700 with accessories and be low to mid 12's. i went dry and have over $2k+ into it with tuning software, wideband, nano, and a lot more. with a stock car and dry kit minus nano, i ran 12.5 on a 2.1-2.2 60', trapped 115 using low pro street tires, no burnout.
a cheap ls1 camaro is likely to have high milage and the rear is probably going to go out. 12's is definitely not hard and knocking down 11's is doable with little money but i personally would not do it without what i deem is proper support.
for me to be dd and try for the low 11's maybe high 10's, it cost/will cost something like this:
$3500 for a rear end
$2500 for a transmission
$2000 for nitrous, tuning software,wideband,ect
$300 for injectors(dry shot)
$700-1000 for wheels and tires(17x11 chrome zr1's with street tires)
$400+ install costs for a torque converter, and cooler
$250 for a fuel pump kit
~10k for the stuff mentioned and more that's unmentioned, you might be able to get everything used for ~5-6k. and everything here is given that a 100k mile stock engine holds up.
otherwise if you can do installs, go
~$2500 heads/cam/intake/exhaust
~$250 fuel pump
~$300 for a clutch(must have an m6)
~$700-1k for wheels/tires(slicks or drag radials maybe)
~$300-400 for a tune
~$600-700 for a wet 100 shot.
do a lot of weight reduction
and pray that nothing breaks and you're in the 11's.
mid 11's has been done with tires, rear end, h/c/i/exhaust, and a good driver. roughly 400whp, a 1.6 60' and trapping 116-119. but that's something i can't imagine that i would manage to do. but it's been done.
this is a deal here, i'm not sure if the guy still has it for sale.
37k mile t/a runs 11.6 $14,900. you would basically be getting a free 37k mile car if you bought what he spent on mods.
http://www.norcal-lsx.com/forum/showthread.php?t=60348&highlight=synergy