You've got lots of options.
STRETCHY WRAP:
My favorite nb carrier. I would feel really lost parenting a nb without one! You can do a cradle or tummy-to-tummy (or later on, a hip carry); the holds are very secure so you're 100% hands-free to do laundry or whatever; good weight distribution; pretty easy learning curve; easy to bf in; poppability - meaning you can pop the baby in and out for those of-so-frequent nb poopy diaper changes without having to take the wrap on or off. Only drawbacks, imo - lots of fabric, so it can be warm in summer; limited useful life, as the material isn't supportive enough for heavier babies (after 12-15 pounds) and isn't suitable for back carries.
Brands: Moby, Gypsy Mama Bali Baby Stretch (pricier, but less stretchy, so will last you longer as the baby gets heavier), Sleepy Wrap, Hug-a-Bub. Or just make your own for $5 out of stretchy material.
For the t-2-t, he can be upright even as a nb. The fabric will support his head.
WOVEN WRAP:
Will last you FOREVER. All the pluses of a stretchy wrap, except less poppble, and a longer learning curve. Can be pricier, but will last forever, and there are bargains available. You'll be able to use these for back carries too, unlike a stretchy wrap.
Brands: Girasol, Didymos, Easycare, Vatainai, Hoppediz, Storchenweige, BBSlen, Merry Carry, Lana....
Or, make your own out of a tablecloth!
RING SLINGS:
Another very popular nb carrier, for good reason. Poppable, not a bad learning curve, great to bf in. Great for cradle carries, a little less hands-free for tummy-to-tummy at the earliest stages; all the weight is on one shoulder, but at the nb stage that's probably fine unless you have 12-pound babies usually.
I am not up on RS brands... I know Eesti because I use her pouch slings, and I've heard good things about her RS too. That's all I know.
You can also make your own pretty easily.
eta: I've heard lots of bad reviews of the NoJo. You may like an unpadded rs much better.
Again, with t-2-t he can be upright; there's enough fabric to support his head.
POUCH / POUCH SLINGS:
EASY to use - not a thing to tie, buckle, or adjust. Poppable as heck. Great for cradle carries. Like the RS, not as hands-free for the t-2-t position early on, in fact even less so than a RS because there's less fabric. Another major drawback is that sizing is crucial - one inch off and it's not going to work optimally. Also not super easy to bf in.
Brands - Slinglings, Hotslings, Karma Baby, Eesti
MEI TAIS:
Workable for a newborn; most people like them better a bit later on though. You do an upright t-2-t with the legs inside the carrier; the body of the carrier will support his head. Not all babies like this position. Medium poppability - you will have to take the carrier off or at the least adjust it each time you take the baby out. Only so-so for bf in. Pluses are it's very supportive and will last through toddlerhood.
Brands: BabyHawk, Freehand, Beanslings, Mai Tai Baby, CatBird, Sachi, Kozy... hundreds of others... I could go on all day. I'm a MT addict.
SOFT STRUCTURED CARRIERS:
My least favorite option for a tiny newborn. They are not very snuggly, and it can be hard to position tiny ones safely. A great option for later down the road, due to supportiveness and ease of use, due to the buckles. Can be used for front or back carries. Some brands, like Pikkolo, can be used for front facing out carries. A compromise if someone really really wanted a buckle carrier for a nb would be something like Connecta, which is more like an MT but with buckles.
For nb carriers, especially one you think you won't be using forever, consider buying used or making your own, if budget is an issue. You can find great deals at thebabywearer.com for used carriers, and here's a link to make your own:
http://www.mamatoto.org/Default.aspx?tabid=63
