wrote:
. . .I have a worksheet called "aliases" as follows:

column a column b
table_name alias_name
customer customer1
customer customer2
sales sales2
sales sales2
site site1

What I need to do is create a function or procedure that takes
table_name as an input parameter and returns all matching alias
values. . . .

If the functions in the freely downloadable file at
http://home.pacbell.net/beban are available to your workbook, you might
consider

=VLOOKUPS("customer", lookup_array, 2)

array entered into a column of cells sufficient to accommodate the output.

Alan Beban