Ithaca
I did a 4 1/2 year tour in Ithaca and can give you this info....
As for camping, Treman is nice, I have never stayed in any of the state parks as I had a house to go home to.
What you should see.....
You mentioned waterfalls...Waterfall and gorges is one thing that Ithaca has tons of. After all, Ithaca is gorges. You will absolutly want to check out Tremans lower falls and the upper Lucifer falls. Taughannock Falls is also a must, its higher than Niagra, but a bit "less impressive". Its about a 3o minute walk in to the falls. You should also drive to the overlook. Buttermilk Falls are popular, but IMO not that impressive, although it is a popular swimming hole.
Ithaca falls is a definite, its off Gun Hill Rd, the easyest way to get there is from the cornell campus. Take Stewert Ave past west campus and make a left down the hill on Gun Hill Rd. That gorge also has a few other very cool falls..... Go to the CU campus and get a map. Find the Alpha Delta Frat and park in their lot. Next to the dumpser, you will find a trail leading down into the gorge, its a 10 minute walk. It will put you under the "famous" suspention bridge. In the summer, just ask any of the students, they know where it is. Once you get down there, have a swim, you can sit in the small cave underneath the falls on the left hand side of the falls. I used to climb up the fall (its slippery) to the next set of falls. There is the remains of 2 hydo electric plants. And if you get there or go over the bridge on Campus road and see that hydo plant, yes kids jump off all 90 feet of it. Also on the CU campus is bebe lake. Its by North Campus. Take a walk around it. There is a small stone foot bridge that is a popular jumping site (at least untill the CU Police get there a chase everyone away for a half hour. Just up from the bridge, one on either side of the gorge are 2 popular cliff jumping spots. The lower was 22 feet when I measured it, and on the other side of the gorge is "Lovers Leap" That one is 42 feet. Lots of fun.
You may also want to ask some of the Ithaca college kids about the 6 mile creek swimming hole. Its a 15 minute walk in. I forgot the name of the road the path is on but just ask, the kids will know. Its the top of a dam, with a great view and lots of swiming chanes. Be careful tho, its been know to have one or two folks show up in their birthday suit.
Another thing I would highly recommend is Stewart park. It is absolutly beautiful at sunset. Its the southern tip of Cayuga lake. if you are there on the days its open, check out the Ithaca farmers market, just off Rt 13. Small, but charming.
Also check out a few of the wineries on Cuyuga and Senica lakes. Reisling made in the finger lakes of NY is some of the fineset in the world. Weimer is probably the most popular. Its about an hour drive from Ithaca on the western shore of Seneca lake.
As for places to eat, this is a bit more subjective. I think that the John Thomas Inn is one of the best steakhouses ever. It is however, biz casual attaire and pricy. Moosewoods was a great place. The Nines is a dive but they make amazing pizza (and im from downstate NY). Its of the deepdish variety. Just a taste is neat tapas and wine bar downtown. One thing I have to plug, if you happen to be in ithaca during the school year, check out TCAB. Its a student run restaurant at cornells hotel school. The students develop and plan their own restuant for the night. It might be great, it might be awful, but it is unique.
The last thing I have to say is that Ithaca as plenty to offer, but you have to look for it. Ask around, the students are full of info. Also, the CVB by the entrance to Stewart park has a ton of info.
I hope this helps and I would also be amazed if you actually read this entire post.
Let me know if you have any questions and how you trip goes
Rob