For baby washcloths, cut up some old t-shirts into squares. If you sew, you can finish the edges, or make them double layered. It's super easy and the fabric is nice and soft. You can use these for wipes, too.
For changing pad cover things, you can use towels, or even a t-shirt. You could also use a rectangle of fleece fabric.
I was just at Target and they had 3-packs of receiving blankets for $6, which is cheaper than I could make them for.
If you can't find 'em cheap, and if you sew, or know someone who does, you can usually find a few cotton flannel fabrics in the clearance section at most fabric stores. Just serge or hem the edges. (You can also make baby wipes/washcloths and nursing pads with flannel.)
If you don't sew, you can still get fleece to make blankets with, just cut it to size.
Assuming you'll be wearing an overshirt (I know I would be- it's cold here!), you can nurse in any tank or camisole. Camis with low/stretchy necklines can just be pulled down. You can wear them under regular clothes and save lots of money on nursing clothes.
Some stores have some camis on clearance right now, since it's winter.
You can also
convert any bra into a nursing bra
Are you using cloth diapers? If you had a fancy kind in mind, consider DSQ prefolds (make sure they're Diaper Service Quality- a lot of "prefold cloth diapers" they sell in stores are just meant to be used as burp cloths and aren't absorbent enough for diaper use).
Two dozen is generally about $40 or less. You can skip the newborn size (the larger ones can be folded down so they'll fit a newborn). You'll need 4 or 5 covers, minimum. Good ones run about $10-$15 a pop, but you can tide yourself over in a pinch with the Gerber covers, which are $4 for a 2-pack.
Also, you can look into thrift stores, consignment stores, and ebay/craigslist. You can find lots of good and cheap stuff that way, and sometimes you can find someone selling everything you need for one lump sum.