I took my first roadtrip with my son when he was 2 months old on a trip that's 8 hours each way. We've taken that trip 3 times so far, plus we've flown to England (11 hours + driving a few hours after that). He went with no troubles at all! The vibration of the car or plane tended to put him to sleep when he was little (now he's in a forward facing carseat and just watches everything out the window half the time). Things we did to make sure all went well: always have more than enough diapers/food because you never know what you'll encounter, we keep a large mirror on the backseat so he could look at himself (and we could keep an eye on him)-you can pick those up at Babies R Us and maybe Walmart, put 1 or 2 of those little infant carrier toys in, don't keep the baby too hot or too cold (one favorite fuzzy blanket worked best for our son), and we kept baby-friendly music on, at least while he was awake: either happy tunes played quietly, or classical music (it's helpful for you to deal with it if you go ahead and buy it in the adult section with "normal" instruments, and mozart's adagios are nice), and now our favorites are the rockabye baby cds (they take old favorites like green day, the ramones, rolling stones, all kinds of "real" bands and play those songs in instrumental versions with "baby instruments" instead of loud guitars or whatever). if you're traveling alone, i suggest a busy truck stop where you can get gas, go to a clean bathroom, and have a cafe give you some hot water (that you add a little to your regular bottled water) if you make bottles. that's just for safety: the rest stops are usually so isolated these days! when my husband and i travel together we make great time because he turns the gas pump on and changes joe's diaper on a change pad in the car(and if there's time exercise joe's legs by bending them and being silly) while i run to the bathroom and get the goods for his meal together, then i sit in the backseat and feed him while my husband runs to the bathroom and gets a snack. organized teamwork helps. i personally think that if there's room, the full sized change pad makes life a lot easier than the diaperbag sized change pad. you can just lay it on the backseat and change with no fumbling around. not only does that make it more convenient and faster than dragging the baby into the store and stuff, but you also don't have to worry about "cooties" in public bathrooms that all too often DONT have proper change tables.
