All major infant carrier manufacturers sell their seats as part of a "travel system." These systems incorporate the infant carrier seat with a large stroller. The carrier seat clips into the stroller rear-facing. When the baby outgrows the infant seat, it is removed and the toddler rides in the regular stroller seat. They're sold as a cost-effective long-term solution for moving around with a baby.
Most travel system strollers are quite large and unwieldy. At the early stage with the infant carrier on board, they are extremely cumbersome. We've heard from mothers that these large strollers, in addition to being nearly impossible to maneuver in stores, are also relatively fragile. Many don't last more than one child.
An alternative to the full sized travel system is the stroller base. They fold to nearly flat and are very light. The disadvantage to this choice is that you'll have to buy a separate stroller when your baby outgrows the infant carrier. However, many moms found the travel systems so unwieldy, they bought new strollers anyway. Being freed from buying a stroller as part of a travel system gives you more options.
It's wise to resist the urge to buy "outfits" at this stage of the game. Babies spit up, drool, and wet themselves a lot so the best thing to have on hand is lots of onesies for summer babies and toasty pajamas for winter babies. Newborn infants must have their heads covered outside in all but the warmest summer months (when they should stay out of the sun, entirely). Have plenty of cozy stretchy hats on hand, too. Many moms prefer babies have their feet covered, indoors and out, so get lots of warm stretchy socks.
Any health problems encountered in the first few months of life means an immediate call to the doctor. You should not dispense any medications to your child without the explicit direction to do so by your health practitioner. However, to spare you midnight runs to the 24-hour pharmacy across town, here is a list of basic care needs you want to have on hand for your baby:
Good luck on your parenting adventure! Remember that no one starts out an expert but with preparation and help, you'll be one in no time!