CGI Scripts for Sale
CGI Resource Index
If you can't find your CGI here, well, it might not exist. These are all hosted remotely, so you don't have to have CGI access.
CGI * StarPro
This program creates the CGIs and the forms for you for an easy way to make an interactive Web site. And if you don't have CGI access, WebGenie will rent space to you.
CGI World not only provides many Perl CGIs, it also will do custom CGI generation.