A lot of excellent suggestions about tent types, but no recommendations of
actual tent brands that are both strong and waterproof.
What tent brands work at OSH and what brands should I avoid?

For the answer to that question, you will get many answers based on
different experiences.
Personally, I am a backpacker, so the brands I know are the higher
priced ones that I know will hold up to whatever I can experience.
Others will tell you WalMart works for them.
If you look at the pictures of the AirVenture, you will see many styles.
You will also want to consider whether you want everyone in the same
tent or kids in one and adults in another.

Criteria for helping you determine what to look for:
- number of people
- shape and size of tent
- materials of tent components
- quality of workmanship and design
- weight
- price

I shop for camping gear online and at local stores and always wait until
the product I desire is onsale. You can save anywhere from 30-80% off
the original price if you are patient. Now is the ideal time to start
watching for three-season* tents to go on sale as many vendors are
starting to place their spring and summer merchandise on clearance.
The following online sites cater to backpackers:
campmor.com (hot deals, web bargins)
rei.com (online outlet store)
sierratradingpost.com (closeouts, bargin barn, web exclusives)
northernmountain.com (killer deals)

Others, such as Eddie Bauer and LL Bean are more geared toward the
recreational campers and Cabellas the hunters.

As to a single manufacturere that I would recommend for a good line of
products and reasonable quality, check out Eureka tents. They also
produce many OEM models for various stores.

The two websites I check daily are campmor and rei.
If you have a child in boy scouts there are some good deals available
from some manufacturers.