Congrats.
Sorry this is so long, there is so much that society (merchants and friends and family) will push you into buying that you don't need. Don't buy anything until you are *desperately* sure you need it! For the first month have the baby in a basket or something by the bed, baby sleeps better than in another room and so do you. You don't need a crib until the baby is mobile (and that doesn't mean walking, mine rolled, then crawled, before she walked, and she could really move). The Tightwad Gazette Volume 2 has lots of baby ideas, and she really knew how to have a happy baby without spending!
Really work at getting enough sleep, I was a zombie the first month while our daughter adjusted. And they do want Mommie, you may end up working away from home for a while.
Easiest way to change a diaper while being kind to your back - put a towel on a counter (bathroom or kitchen) with all your supplies handy, change baby, put away (or leave out if you have the space). Having running water handy is good if the bum needs extra cleaning. If the baby is a boy, pop a cloth over the front while you are changing the diaper - I had a girl, but my sister got a faceful one time! And diaper services are more expensive than washing your own, unless you spend a lot of money on cloth ones, but still a lot less expensive than disposables. And they adjust to demand - using more? They give you more. Need the next size up? They are ready for you. We were on a well and I didn't want to use that much water, so that was the route we went. When I went back to work, our daycare was fine with cloth, I just brought them and took them away each day.
The best thing we did was put a dimmer on the bathroom light - middle of the night we would breastfeed one side, go change diaper with just enough light that I could see what I was doing, which meant she didn't wake up all the way, and then do the other side. She usually fell asleep doing this, and so did I, so have a really comfortable chair for nursing. And breastfeeding makes a baby a lot more portable, she was so easy to take anywhere because as long as I was around there was no food to worry about. And less diaper rash and poops don't smell as well.
As others said, go for used clothing, babies don't wear it out. And they don't need shoes unless they are walking outside on hard surfaces. As they get older, the clothes that don't wear out are the expensive party/holiday ones, so that is a great place to buy used. I have picture of ours at 4 and 5 in her red Christmas dresses with the lace collars (one each year, she grew) - second hand, in wonderful condition, she wore them maybe three times each? So someone else ended up wearing them and they were still in great condition. And don't buy anything much at first because you will get gifts.
Have fun and enjoy your baby.