Itemnum field

[Katrina Morris]

Hi,

I would like to create my own javascript alert when customers fail to select
any items before clicking on the add to cart button, rather than submitting
the form and getting that generic page that is generated. Here is one of the
pages I would like to do this for:

http://www.rexart.com/loe_american_painter_4000.html

Any suggestions?

Thanks,

Katrina