Rob Scofield did a great job organising the Amersfoort meet - I think some tips could be taken from that event.

Essential:

Easy to find location and/or roadside direction markers on the day
A flag or banner to indicate the meet site
Plenty of parking space without major sound restrictions
A nearby indoors area with refreshments available
Nearby restaurant(s)

Cool Ideas:

Best installation competition (everyone votes)
Empeg geek quiz (questions supplied by empeg)
Technology preview by empeg (if we can make it!)
Prize for the attendee that drove the furthest for the meet

I suggest you agree on a date soon - if anyone from empeg is to attend we'll need plenty of notice.

Rob