Even though you won't need the full stash of bottles you'd need if you were formula feeding, there are some supplies you'll need if you're planning on breastfeeding. 

Breast Pump

If you plan on leaving your baby for any amount of time during the first 12 months, you'll need a breast pump.  The type you'll need will depend on how often you'll need to pump.  A mom who will be at home with her baby most of the time can get away with a manual breast pump , while a mom who works outside the home will need a high-quality electric pump. 

Manual Pumps

   Manual breast pumps require you to do the pumping by squeezing a handle.  You have to pump one breast at a time, so using one of these can be time-consuming.  On average, you can expect to pump each breast 10-15 minutes using a manual pump.  These pumps are fairly inexpensive. 

Electric Pumps

Electric breast pumps can be a working mom's best friend.  Both breasts can be pumped at the same time, and the only thing you have to do is hold the collection bottle in place.  Pumping time is cut in half compared with the manual option.  Most women report being able to pump more milk using an electric pump.  Most electric pumps also have different speed and suction settings so you can find the setting that is most comfortable and productive for you.  Manual pumps can be very expensive, so unless you will be pumping more than several times a week, it probably won't be cost effective for you to purchase one. 

Milk Storage

After you pump your milk, you'll need something to store it in.  If you plan on making a large stockpile of milk, you'll need a great deal of storage containers.  There are essentially two types of storage systems: bags or containers.  You'll need to experiment to see which system you like better.  Bags take up less room but can be ackward.  Containers take up more room but can be reused. 

Bottles

Unless you plan on nursing your baby 100% of the time, you'll need at least a few bottles.  How often someone else will be feeding your baby will determine the number of bottles you'll need.  There are many, many types of bottles on the market, some marketed directly for breastfed babies.  Avent is popular among breastfed babies that I know, and is what we use in our house. 

Nursing Pads

The first few months you are nursing, your breasts will likely be unpredicitable. Many moms leak milk at inconvenient times.  Nursing pads slip into your bra and absorb the milk that leaks out.  Cloth pads or disposable pads are available.  Cloth pads may be a more cost-efficient option because they can be reused.  Disposable pads can be expensive. 

Nipple Cream - Lanolin

Breastfeeding moms often have sore nipples, especially at first.  The best thing for this is lanolin .  There are several brands available, but whichever you choose be sure that it is 100% lanolin.  Even though a tube of lanolin can cost about $10, it will last a very long time.  Lanolin is always a good thing to have around with the baby as it can be used for diaper rash or other skin rashes. 

Nursing Bras

Every breastfeeding mom will want to have a few high-quality nursing bras.  You may want to wait to purchase these until after your baby has been born because your breasts will likely change size as your milk comes in.  Nursing bras look like regular bras, except that the cup folds down to give access to the nipple. Some nursing bras can be very expensive, but truthfully I've had the best luck with moderately-priced brands like Motherhood. 

Nursing Shirts

If you plan on nursing outside of your house, a few cute nursing tops are great to have.  The shirts have panels that can be removed that allow breast access while at the same time providing ample coverage. Nursing shirts also tend to be a little roomier in the chest and tummy areas for your postpartum body.  There are many, many styles available. 

Nursing Pillow

It can be difficult, especially at first, to find a nursing position that is comfortable for both you and your baby.  A nursing pillow can help provide support for your baby and give your arms a break.  Again, there are many brands and styles available that you'll want to check out. 

I hope you have found this guide useful.  If you haven't please let me know!  Thanks!