I'd recommend buying two of the following:
Vibrating bouncy seats (get four if you have two floors to your house)
Pack 'n Plays if you plan to travel at all (most hotel cribs we found were unsafe)
Baby Bjorn front pack carriers (FANTASTIC)
Also, get a double stroller. We had one from Maclaren that was great. My kids fit in it until they were 5, though we mostly used it from age 0-4. In contrast, they outgrew their single Chico strollers by age 3.
Buy one or two of the following:
My kids didn't use their boppys, and I wasn't ever able to breastfeed them, so the EZ2Nurse pillow I'd bought was never used. YMMV. If you are able to breastfeed, the EZ2Nurse pillow is a good idea.
Also, if you plan to bottle feed at all (either expressed milk or formula), don't buy the bottles with huge nipples (like Avent). I had only Avent bottles, and we had to run out and buy a bunch of Gerber bottles with the tiny nipples because my kids couldn't handle the huge ones. The Avent microwave steam sterilizer was great for all kinds of bottles.