Just got back from a week long trip to Gettysburg, PA. We stayed at the Drummerboy Camp Grounds. It was the off season so the rates seemed pretty reasonable, 4 nights was just under $200. They were accomidating and let us check in at 1300 instead of the normal 1500
We stayed in a premium slot (drive through, mostly level, wooded, cable, sewer, water, and 50/30A). I did not experience any electrical issues and did not have a surge or line conditioner since this was my first time. The site had a fire ring and picnic table. The slot was mostly level, slight downward grade from hook ups towards the front of the trailer. I will bring leveling pads next time as I maxed out my jack. The trees had not quite grown their leaves so the trees did not provide much privacy, but we had decent spacing. A couple of the other places I looked at were compact and wedged everyone in like sardines.
The campground is to the east of the town of Gettysburg about 5 minutes from the Battlefield and the town. You can take the highway to avoid the town traffic. They offer a military discount. There is also free wifi during the off-season which had decent coverage and speeds. They also have a pool but does not open until May. Other ammenities are public bathrooms/showers, snack bar, mini-theater, playgrounds, tent and picnic areas, cabins, free fishing lake, and emergency grocery store. They are also pet friendly, except in the bathrooms/showers.
We did not expect to spend a whole day at the Park's Battlefield visitor's center. There is parking for trailers/buses at the visitor's center but would avoid it if possible. We also spend a day touring the battlefield using the audio tour CD and were only able to hit half the sites. I suppose if you do not stop and get out at each site (and without kids) you could finish it in 2 hrs.
The only other museums I liked was the Gettysburg Diorama and my boys 7 and 11 liked the train museum. The rest of the museums seemed like people cobbled together a bunch of stuff they collected and charged addmission.
If you want to do the Battlefield I would plan on 1 day for the visitor center, 1 day for the town sightseeing, and 2-3 days of the battlefield. I recommend you bring bikes so you can park your vehicle and ride your bikes on the paved trails. While you can drive parking can be a problem during the peak season.
For a nice lunch I recommend Eddie's Bar/grill. Their crab dip was excellent. If your kid's are 12 and younger get the kid's meals. They are half the price and the same size as the adult's (at least the hamburgers were) plus they get a desert. The other sandwiches are decent, nothing earth shattering.
There was one grocery store in town called Kennie's and had most common items at reasonable prices, but if you are looking for ethnic items better bring them yourself. There was also a Walmart nearby as well. RV parking is limited to 1 hr there. Plan to drop your trailer then get gas. Most of the gas stations are very small. Only the Sunco is big but the turns are tight if you had to get a trailer to the diesel pump.