Nested SQl With Count, Percent And Joins: How?!

Hiya,
I have a need for a complex SQL statement to provide reporting information, but the SQL is way over my head and although I have some of the elements, I can't seem to pull them together to create a working SQL statement.
My database structure is as outlined below:

tblDef
------
ID IRVitems
ABC A1,A2,A3,A4,A5

tblIRV
------
ID IRVvalues
001 1,5,text1,10,3
002 2,1,text2,1,3
003 2,4,text3,1,1
004 1,4,text4,4,1
005 1,2,text5,4,1

tblLabel
--------
lblID lblVALUE lblTXT
A1 1 AAA
A1 2 BBB

I currently query tblDef to get IRVitems and in turn then query the other two tables to get statistical information to present in a report (via ASP).

For each item returned from IRVitems, I would like to report the spread and frequency of different values as follows:

A1
Value Label Count Percent
1 AAA 3 60
2 BBB 2 40

and then for A2, etc (although missing out A3 as it is a text item, but I can deal with that via ASP code beforehand). I would expect to have to hit the DB for each of the IRVitems (so once for getting the data for A1, againfor A2, etc).

I was provided a great bit of code to use SUBSTRING and GROUP BY to get this data (thanks zuomin), but I didn't consider the possible text values or numbers >9 when defining what I was trying to do (to be fair, they're new requirements):

SELECT SUBSTRING(IRVvalues, 1, 1) AS Value, COUNT(ID) AS Count
FROM tblIRV
GROUP BY SUBSTRING(IRVvalues, 1, 1)
ORDER BY value

which returns like this:

Value Count
1 187
2 163
3 2

Can I do a similar query to get all the info I need in one go? I saw the articale on a user-defined 'split' function (http://code.msdn.microsoft.com/SQLExamples/Wiki/View.aspx?title=StringArrayInput&referringTitle=Home) that can be used to split up the IRVvalues string to access the position I need in the array, but I'm a little clueless on how to then embed that into a SQl statement.
Can anyone point me in the right direction please?