You are in luck.
As you may know, the iPhone touch screen does not respond to tapping at all. It also does not react to anything that you decide to touch it with.
This is because it works using a technology called capacitive touch which measures the flow of electrons through your skin.
A quick Google search turned up a number of them, this is just one:
http://www.thinkgeek.com/electronics/cell-phone/a31f/ but the price is a little high.
Amazon, link below, has a whole bunch of them for a lot less.
http://www.amazon.com/s/?ie=UTF8&keywords=stylus+for+iphone&tag=googhydr-20&index=aps&hvadid=4307780687&ref=pd_sl_7xvxfroh2p_e
Hope this helps you
P
I am stuck with an iPhone because of the plan my husband subscribes to. I love all the apps, but have arthritis in my fingers and thumb and often my fingers are too cold to open the app quickly. Last week I misplaced my iPhone and went to the store to have my old Samsung activated. The small flip phone was a dream to handle compared to the iPhone. Within a day, I found the iPhone, and found that now I don't want to give it up either. The ATT sales said that there is a stylus available, that I know would really help me. The Apple store sales person looked off into the sunset when I asked about it. Does anyone have any ideas. Thanks so . . . much!

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