M.B.
what's the rush? sounds like neither you or your son are ready to wean. looking back, i wish i had breast fed my kids longer (i did for 10mo, 8mo, and 10mo). i plan to breastfeed this one for at least a year and am open to breastfeed until the baby's ready to quit. the average age of weaning internationally is 5-7 years!!! that doesn't mean you have to breastfeed that long, but you can pump and provide milk for him. north america has some of the healthiest kids in the world. and one of the lowest lengths of breastfeeding. think how much healthier our kids would be if we all breastfeed longer.
you did mention wanting to quit by October. was there a particular reason why? whatever you choose, i'm sure it's for the best for you and your family.
but here are a few sites that might help you in your decision.
normalfed.com --there is advise on when to wean here too.
http://www.drjaygordon.com/development/ap/sleep.asp --this website has good info on sleep patterns and comfort needs. with regards to night time feeds too.
good luck with everything. and be confident in the choice you make. i'm here, as well as others i'm sure, to support you with whatever you choose.