Hello! I did indeed visit last year (once for the 24 and once for a Blancpain round) - have to be honest I didn't camp for either though so I can't really help you out there. I may ramble here - sorry.
Let's get the slightly boring stuff out of the way first...
Regarding camping I will say, from just experiencing the place if you actually want some sleep don't camp on any of the campsites actually around the edge of the main Nordschleife. I believe Travel Destinations has a campsite on the edge of the GP loop which is supposed to be a bit friendlier. Alternatively if you don't mind driving a bit then it is possible to find accommodation nearby. Me and my friends left it very last minute, as I was supposed to be going to Imola that weekend then had a change of plan, so we organised the entire trip in 2 weeks and found great accommodation about 40 minutes from the track.
Plus side of finding hotel/B&B/whatever is that it's pretty easy to drive to different locations around the track rather than walking. They do a neat deal with the car parking which means you pay something like €20 which will get you in any of the car parks for the entire weekend.
Food wise, it's not hard to find something to eat. The pubs and restaurants in central Nurburg will be rammed obviously so if you were thinking about visiting the
Pistenklause then book it now! I didn't get to visit Pistenklause during the 24H but when I visited again for BES I loved it. The place is incredible with some incredible racing memorabilia on the walls of the place - and the steak on the stone is an absolute classic. The pizza they make isn't half bad either. Other than that there are plenty of food places around the circuit for typical currywurst or burgers and chips. There are some food places inside the Nurburgring Super Mall thing too which is easily accessible. As for drink...yeah, you won't have a problem finding that.
Obviously, the further out you travel from the 'Ring the more pubs you'll find that are less busy. There are some really nice food places out there though - try and brush up on your basic German before you head out though (we had an awkward moment where we didn't speak German and they didn't speak English)...
Anyway - now the fun stuff!
As soon as you get to track - and before you even watch a car make sure you go to the petrol station on the Dottinger-Hohe and buy yourself an €8 euro map of the track - it's really rather detailed and will help you find car parks, paths and tunnels. We found it massively useful. It's worth mentioning the petrol station also sells some hot food which is useful in the middle of the night when there's a rain delay for example... Also if you collect model cars ignore the left hand side of the shop. I'm saving your wallet - you'll thank me later.
It's worth getting into the paddock one time before a practice session begins - we went on the Friday which seemed to be a good plan. If you get there early enough you can see all the cars in the garages, some teams (particularly the smaller ones) might even show you round the facilities which can be quite interesting.
But as soon as that's done head out onto the Nordschleife. There's some much to explore out there that wasting time at the GP loop seems a bit silly really. My favourite bit that I walked was from Brunnchen to the Karusell, lovely scenery but the atmosphere is incredible. The campsites are built so closely to the track that it almost becomes like a little medieval town. Karusell is a little overrated from the inside (big fences) but it's still worth seeing, looks beautiful in the afternoon/evening light. You can also the walk from Brunnchen to Schwalbenschwanz (basically the opposite direction) is pretty stunning too as you'll pass plenty of 'lift off' spots including Pflanzgarten (which is far more impressive than Flugplatz - and easier to get too) but they also lift a wheel or so a little further down the road. Pflanzgarten is full of incredible structures from the fans too. Handily there's a well placed car park at Brunnchen so I'd definitely suggest heading there. I also watched the start from Brunnchen which was pretty impressive.
View from Brunnchen at the beginning of the race
Another great walk is from bridge (at Adenau) towards Metzegesfeld - some truly staggering views along this route. Honestly the best you'll ever see with circuit racing.
One of the stunning views from the walk towards Metzegesfeld
Also, just because you have to do it - a walk along the Hatzenbach section of the circuit is a must. The campsites are extraordinary here and I imagine the place comes even more alive at night, but we never had the chance to experience that due to the rain.
During the middle of the night, assuming it'll be dry this year, I'd try to get to the GP loop just to watch some pit stops from the grandstand and have a bit of a break. Should be plenty of food places open around there too for a midnight snack. Also, I'd try and get back here for the finish - I missed out on this and wish we had made it there in time, that said the atmosphere of the finish is good around the entire circuit.
In regards to equipment, I think it goes without saying, be prepared for everything. Good walking boots are an absolute must - if you like getting good pictures you'll move around a lot. Waterproof jackets (that are quite light to carry - it can be really rather warm too) are important too as are waterproof trousers.
Must be said, unless you have a great signal in the forests (and good abroad data allowance) it's probably rare that you'll have any kind of idea what's actually going on in the race. The commentary points around the circuit are pretty poor (and in German) but if they aren't saying any information they'll be playing 80s pop music. RLM aren't broadcast on an FM frequency like at LM so it makes things a bit difficult. But to me this event is all about the atmosphere anyway.
Anyway, I realise I've gone on a bit. If you want more details of particular stuff or photos from particular locations I'll happily help anyone out as much as I can. It's definitely an event you need to do - I honestly loved it more than Le Mans. Totally different event but well worth the visit.
It's not so much the bank balance. It's living up to the challenge of the adventure! Right now, my chariot of averageness is without MOT or Tax. I myself may or may not have a driving license, depending on a letter I hope to get soon from the DVLA. I don't speak French, or German... I've never driven on the right, and I've not been to any of the destinations I'm aiming for before and I'll be travelling alone... pfft... Money? That's the easy bit 
