find value in matrix (in other words: find value based on 2 criteria)

Hi, i am trying to make excel Calc find a value in a table i have in the same spreadsheet, that matches 2 conditions.
I am trying to make Calc return the “maximum load value” of musical instrument strings based on “diameter” and “type”

My table looks like this:

diameter |     type    |  max. load

0,7_____________1_____________x

0,75____________2_____________x

0,8_____________1_____________x

etc.

The data, consisting of “max load values” looks like this:

diameter |     type 1    |   type 2 | type 3

0,7_____________500____________600____750

0,75____________550____________660____820

0,8_____________600____________710____870

etc.

how do i find “x”?

If you have your data like this:

Sheet1

	A		B		C
1	0,7		1		<Formula>
2	0,75	2		<Formula>
3	0,8		1		<Formula>

Sheet2

	A		B		C		D
1	0,7		500		600		750
2	0,75	550		660		820
3	0,8		600		710		870

… then you can use this formula in Sheet1.C1: =VLOOKUP(A1;$Sheet2.$A$1:$D$3;B1+1;0)

this works !

The index part of vlookup function is what i could not seem to figure out.
So, thanks for the help !

kind regards,
Lander