Well, no one else is answering, so I'll give it my best shot.
My son had a terrific experience at a PG showcase he attended last summer. The PG staff was very professional and everything ran seamlessly over the 2 days. I believe they use lasers for the 60, which makes for a more accurate reading. It took a few weeks for the results and rating to be posted, from what I recall. The rating is helpful for parents to get objective feedback on their son's potential. The written evaluation on-line is a condensed version of what can be found on PG Crosschecker under your son's name (Crosschecker membership available for $200 annually). Written feedback, plus any honors such as selection to the showcase's Top Prospect Team, can be included on a resume sent out to college coaches.
If your son is an underclassman (class of '09 or later), he might want to attend one of the underclass showcases. The South Underclass Showcase will be held Aug. 11-12 at Baylor. If he's a rising senior, he might want to try one of the Sunshine showcases in June. It is my understanding that top prospects at the Sunshine events are selected to attend PG's highly-esteemed National Showcase, which reportedly is teeming with scouts. Here's the link for PG's showcase schedule:
http://www.perfectgame.org/schedule/2007/Regarding college events, choose carefully and attend only at those schools your son is interested in playing for -- unless he's invited to the Stanford camp! And ask around about others' experiences at college camps/showcases you're interested in, as some camps can be a ripoff. You can post a question about a particular school on this site.
If I were you, I would have my son attend both a PG showcase and one or more college events.
Best wishes on the recruiting trail!