Is there a VBA equivalent of GET.CHART.ITEM?

I have an 'area' type chart and I'd like to have two arrows that can be
moved and then based on those arrows another chart is generated just
using the values between the two arrows.

So something like this


| _____|_______ | /
| _ / | \ | /
| / \___/ | \ | /
|/ \|/ \____\|/____/
-----------------------------------------
1 2 3 4 5 6 7 8 9 10 11

So a new chart is generated using the values between 5 and 10.

Now after reading parts of Stephen Bullen's book
www.oaltd.co.uk/ProExcelDev I've been able to do this using pixels, but
I'd like a safer method. The GET.CHART.ITEM can do what I'd like for a
column type chart, but the link to the MS KB article is dead so I don't
know what all GET.CHART.ITEM takes.

Anyways, is there a better way to do this than pixels? Will
GET.CHART.ITEM work? Does somebody have documentation for
GET.CHART.ITEM?

Thanks
James