Nipple cream is a must! It soothes my sore nipples when I first started breastfeeding. I used Avent too.
I find nipple pillows expensive. I used my pillows instead.
You need breast pads for leaking milk. There's disposable and washable ones. For disposables, I find pigeon ones good. I'm still experimenting with different brands of washable breast pads. I've yet to find one that I like.
Nursing bra. You can get them from Kiddy Palace or online. I found some blogstores selling at $12.
If you are pumping, you need to buy storage bottles or storage bags. I used Avent VIA cups to store because after I stop breastfeeding, I can use it to store mashed up baby food when he starts to wean.
-Breast shell: For collecting leaked milk or to air your nipple. You can store the leaked milk if you leak a lot. If you have sore nipples, it helps in airing your nipple and your nipple will not be in contact with your clothes. I used Avent too.
-Nipple shield: I dont't find it useful. I just tolerate the pain on my sore nipple when my baby latch on. The pain is only the initial part of the feeding. It diminishes as he feeds.
You will realise I use a lot of Avent. This is because I bought my Avent dual breast pump from motherhood fair last year. I think for every $50 there's a lucky dip. So the expensive breast pump entitled me to many many lucky dips. I got breast shell, nipple cream, nipple shield, 4 milk bottles, pacifiers, diaper cream, moisturising cream, liquid talc, a diaper bag (it's nice!) and a rice cooker. It was really worth it. Hopefully there's such a deal again.
Btw, show your NTUC union membership card and get 30% off all philips products at philips showroom, includiing Avent products. =) Do ask for the promotion. They didn't put any signs when we went. guess they dont't want to make it too open. lol!