Too many items for one reply so I'll pick a couple and work on those. First I have a house 20-25 minutes away that I can put some folks up in. Camping on the grounds is fun if you're into that sort of thing. I have a tent for borrow if some want to do that.
Dry suit hoses are no problem I have a tub full and DUI will provide them as well but if you're ready to go it's just easier.
There is a big air fill station on the premises. As well as canned nitrox (no special mixes) look at Dutch Springs for current rates. PIR8 has a dive shop he uses and mine will more than likely be there as well. Plus the mentioned Lehigh valley shop is very close. Any needs or wants in the rental category can be arraigned as well as a drysuit course over the weekend if you want.
There are many good eateries and watering holes in the ABE area. (Allentown, Bethlehem, Easton)
I just got off the phone with my dive shop and if I can come up with some idea of the gear people would like to rent he will tow his big gear trailer to the quarry that day. It is a very neat set up.
Umm.. a house is good. Perhaps a silly question, but is the air fill station free? My local DS charges $3 per tank, which is more than reasonable, but i'm unsure how other locations do it.
How much would the dry suit course be (and what agency provides it)?
I'll defer to the group with regards to eateries, but I put my vote in for a pub type set up. They're fun, always have decent food, and cheap.
No Dutch's air is not free, sorry that I don't know their prices, but I don't think they're cheap. I can do the course for $225 if you want it. Includes book and cert card. I usually do it threough PADI but can also do SDI if you prefer. I would say NAUI but I never sent that one in even though I am one of their Instructors also.