There are non within about 25-30 miles of New Britain. How long are you planning on staying? Do you expect visitors?
The reason I ask is that for an extended stay (more than two weeks or so) I would recommend "Wilderness Lake" in Willington, CT. It is a Passport America CG so you can save a few bucks there if you are PA, and the visitor restrictions are not as bad as most. Some 50Amp, most 30Amp, and if there for more than a week, Honey wagon pump out was free. Almost all CG's in CT charge from a few dollars to $5 or more per person for visitors just to visit, not stay over. I think this stinks but too many have taken advantage of them and fill the CG's with visitors and ruin it for just someone to stop over for a burger and a beer.
The closest one is "Lake Williams CG", in Lebanon, CT. It is gated to the extreme. The owner is obnoxious, the sites are grass, tilted, and muddy, and only a dump station, and plenty of poison ivy, some 30Amp sites. Went there five summers in a row and got treated like he was doing me a favor taking my money. I will never go there again. He is also PA but only for one day. Close to route 2 and easy to get to New Britian, but don't recomend it. There is another in Lebanon about 5 miles further (for got the name) but last I knew only 15 amp sites, and very small sites, but very clean, neat, swimming pool, and very nice people running it, but too small sites for my rig.
There are others in Willington, but only 15Amp, small sites also, and very crowded on the weekends.
There is another in Northampton, CT, that also have very small sites, 15Amp and very vistor restricted, and very crowded.
I haven't tried the ones near the coast and the Casino's yet, but they are much more expensive.
If I can be of further help, just fire away.
Hope you enjoy you stay in my home state.
2003 Newmar Kountry Star 3614, W22 248 WB, Banks Stinger & Ottomind, Motosat HD LCD TV's, WD, 58K "Home is where I park it" Walt