You may want to start by looking for scripts that are available at http://hotscripts.com
and you may find some that suits your need.
If you are looking for customised solution, you may want to choose what platform you are comfortable in.
If you are comfortable in UNIX environment, I will suggest a combination of PHP and MySQL for scripting and database. You can also use Perl for scripting. PHP can seamlessly integrate with MySQL due to the fact that PHP has built-in functions for you to do stuff in MySQL
If you decide to go for Windows server, then ASP is probably the best choice.
Dreamweaver Ultradev comes with ASP, ColdFusion and JSP support, so if you intend to use PHP, you can't really use Dreamweaver Ultradev. You have to use a good text editor to write your PHP code. Suggested text editor will be BBEdit for Macintosh and UltraEdit/TextPad for Windows.
Just as a reference, I have Dreamweaver Ultradev 4.0 for designing web sites. When it comes to database solution, I use PHP/MySQL since I'm more comfortable with UNIX environment.
If you have any problems with PHP/MySQL, you can check out the following forums that I frequently visit:
Hope this helps.