I am looking at a site which would allow my users to fill out a questionnaire and then could use a HTTP POST to a script to my site and populate the FM DB. My question is: could I use HTTP POST to populate a server side script which would take that information and put it in to a FM DB? I know this is possible with *Sql, but not sure about FM as I 'm fairly new to the FM family.

Thank you

To have a web form interact with your database it needs to either use the web publishing engine or one of the plug-ins that allow for bi-directional communication between the web viewer and your database. The two that I know of (there may be more) are MBS Plug-in from Geist Interactive and the Fusion Reactor plug-in from Digital Fusion. You might be able to do the same using the SmartPill PHP Edition plug-in from Scodigo.

I believe the OP may have been referring to members of the general public navigating to a site, filling out a form and then having that submit to their FM database - the only reason i mention this is because i'm not entirely certain how the plugins could help here.

It is possible yes, but you'll need to either use the CWP publishing engine directly via its XML interface, or otherwise if you want to keep things clean and simple with the FMAPI or the FX.php class. The only issue here is that you WILL need FileMaker Server 9 -> Though if you aren't currently hosting your database on a server version you could host it online at a provider such as pointinspace.com or fmgateway.com

PS Corn, I love your website.