Finding, searching, and comparing cells to another sheet
 

I'm trying to do a complex formula to search through a column of cells(Part
#), find matches to another cell on a separate sheet(Sheet2-Part#). I then
want to compare the dates(Date) of all cells that match, and tell it to use
the number(Cost) associated with that part # on the second sheet.

So 2 sheets...

Sheet 1 (Columns)
-Date(A1)
-Part #(B1)
-Cost(F1)

Sheet 2 (Columns)
-Part#(B1)
-Cost(06)(C1)
-Cost(07)(C2)

What I'm trying to figure out is how to tell Excel to check the dates so
that a part# dated after 2007 will not be taken into account in the 2006
column, not to account part#s before 2007 in the 2007 column, and how to tell
it to take information (Cost from sheet1) from that specific date's row.

Any help with this is greatly appreciated. As a side note, apparently this
is possible when using Microsoft Project, but being that i have no experience
with that program, i wish to use Excel. Although, any information for doing
this in Project is also appreciated.

Andrew M.