Sorry kara I think I have to disagree. I started LO very early with independent sleep, I'm not saying all is perfect, it's not, but I think it's an on-going process as they grow everything changes, things disturb the pattern (jabs, growth spurts, seasons changing etc) but my LO has been able to fall asleep alone (when he is not ill or some other disturbance) since just a couple of weeks old. I did hold him when he needed holding but always put him down and always made sure there was at least a little A time before S. Initially he still woke for a NF or two but slept about 5 - 7 hrs from almost the beginning and stopped his own NFs by about 7 wks or so.
Having said that, I think people need to do what they need to do. Me saying DS was sleep trained very young doesn't mean that I've never APOP and doesn't mean that he never has any problems. Then again my DP still has problems sleeping and he's 40 ;-)
Eshea, just make sure you check out safety aspects of slings as some of them are not a good design and there were some suffocation issues with them (baby all curled up and face in parents body). They were the diagonal sling type, they look great but the safety put me right off. You might prefer the wrap type which I believe are safe. I used my baby bjorn for LO from as young as possible whilst still following the weight/length guidance (minimum 8lb. My DS was only 6lb 13.5 at birth)