You can find a list of hotels near to the Expo site here:

http://hotels.english.ctrip.com/Domestic/ShowHotelList.aspx

Depending on how long you and your friends are here for and what else you plan to do in Shanghai, you might want to consider staying downtown and traveling over the the Expo instead. It's easily accessible from the the Puxi side of the river. You can find various info here:

http://www.chinatravel.net/Forum/ForumList.asp?Forum=55

In answer to your other question, yes there are long waits for many of the pavilions (think 2-5 hours). You might want to consider booking a group tour ticket to help with this. Check out a few of these options:

http://pages.english.ctrip.com/promo/Activities/expo_shanghai/index.html

The tours get you to the site and back, plus guarantee you entry into the China Pavilion and other "hot" pavilions. You'll be free to spend the day exploring by yourself and just meet up for the reservation times.

You also might want to check some of our tips for queue dodging:

http://www.chinatravel.net/forum/Shanghai-Shanghai-Expo-Tips-and-Tricks-on-Queue-Avoidance/3926.html

Have fun!

Wow, that's a lot of information to take in! Thanks!

There's a cheap good hostel right by the Bund, you can catch ferries directly to the Expo from the Bund, it's called the Captain Hostel, check it out here:

http://www.chinatravel.net/china-hotels/captain-hostel-/introduction-35.html