I tried a few of these sites back in my single days and met a couple of nice girls but everyone misrepresented themselves and their personality at least a little. I don't think I did but maybe that's just instinctual to some extent and we just don't realize we're doing it. I'm kind of socially retarded, so even though I communicate okay online I lock up in social settings unless I'm with a group of people I know well. That probably made some of the online dates a little more awkward than they should have been also. I was more suited to double-dates with friends and such. I eventually met my wife through a good friend of mine (they used to work together) at a cookout he was having.
Most of these sites are geared toward a serious relationship or hookups. It sounds like you're not looking for either, so I agree with others that have said just getting with a group of like-minded individuals and hanging out is probably the best approach to keeping busy and getting out of the house. This way no one is looking to hook up or date necessarily, just out having fun.