the wrap I am using is made of a lightweight cotton gauze.. it's a great beginners wrap and it's the same fabric as the 'sassy wrap' (retails for 75 dollars but I made mine for much less than that). A lot of the mamas here are raving about the 'cuddly wrap'
http://www.cheekymonkey.ca/CuddlyWrap.htm which is a stretchy wrap ike t shirt fabric. the moby wrap is similar. I understand that the stretchy wraps are great for newborns, but as you baby gets heavier they will feel less secure.
I can still wear my 2.5 year old (45 lbs) with the gause wrap doing a back carry with it wrapped around an extra time. I want to get a better woven wrap like the didymos
http://www.didymos.de/english/index_e.htm for more support though- I found that the gauze isn't supportive enough past around a year really.
I's very very comforatable, because you can spread the weight over a much larger area, and adjust it perfectly so that the baby is well supported.
do you sew? I could send you instructions to make your own wrap quickly and easily... I have made both with and without sewing.
If you want to learn how to use a wrap come to the next NINO babywearing support group... I am pretty good with the basic carries!