OK I'm not really qualified to answer because I don't have any kids, but I feel like everyone around me is pregnant so I have observed a lot.
You will not believe how much you will get for the baby shower. Wedding showers don't compare because it is so much more fun to pick out baby stuff than boring wine glasses. My cousin listed "Target gift cards" and EVERYONE got her a gift AND a gift card. People will go in on the stroller and car seats and you will get more clothes than you know what to do with. Leave the tags on in case your baby is big or small. People might buy you summer outfits in 6-9 months but your baby might need 12 month at that time of year. Some people try to wash everything to get ready for the baby, but all you really need are some onesies - you can wash a lot of baby clothes in one load!
Also, for diapers and bottles and pacifiers... there are so many brands and shapes and sizes you will not know what you need or what will work. Some people swear by those Pampers Swadlers, other people are fine with the Target brand. You just don't know. Plus, you'll get tons of diapers at your baby shower. I've heard that you can return diaper packages for store credit if you need to! A friend told me that she bought 5 different kids of bottles and her baby will only use 1 kind. Of course she washed all of them before she had the baby...
Send in for coupons! There are whole websites devoted to new moms that list free stuff you can get from companies. Buy a Sunday paper every week and start clipping diaper coupons. Free stuff is good! A co-worker's baby had to be on an expensive soy formula and the doctor gave him a whole case of it. Don't be afraid to ask for samples!
You are doing the right thing - you have the crib and the bassinet. Paint the walls. Wash the crib sheets. Do the sort of stuff that you can't do later. You can shop for cute clothes and diapers and bottles later
Finally - get a boppy pillow. I don't know what it is, or what it is for, but apparently they are awesome.
And buy special dog treats so the dogs don't feel left out. Oh and the baby sounds CD they sell especially for dogs!