You need a web server a database and a method of accessing the database and formtting the output as a web page. Looks like you are there already with Apache, MySQL and PHP4
To a certain extent the choice of tools is up to you and depends to a certain extent on what you are familiar with. If you are sued to VB & VBA then an ASP rather than PHP site may be easier to gets to grips with.
You can use JET (Access inbuilt data engine), but I wouldn't reccomend it if your site will be failry active. I have used Access as a means of doing the site data capture and then moving the data periodically into MySQL using dbTools (www.dbtools.com.br)
If you go down the PHP route there are lots of resources available to assist the development (phpclasses amongst others)