I recommend trying the forkmanager perl module. I think it might accomplish what you're looking for. hxxp://search.cpan.org/~dlux/Parallel-ForkManager-0.7.5/ForkManager.pm For some research, maybe try these sites.
hxxp://www.unix.org.ua/orelly/perl/prog3/ch17_01.htm
hxxp://earth.e-raist.com/~raistlin/coding.html
hxxp://bfr.caseywest.com/archives/005438.html
I got that from my job of web hosting. I'm not sure of any ebooks though. I hope that helps.