Where do you find FREE public records online?

I need some help with a little situation I'm in. We had a garage sale a few months ago and some people that live around the corner from us came to check some stuff out. Anyways they came up to us and started making small talk about things in general(I wouldn't say we hit it off). The guy then said after a few minutes of that that we should start hanging out. I didn't know what to think or say so I just said maybe we could sometime. Well I ran into him a few times here in there and he always seems insistent that we hang out. In one of the conversations we had the UFC came up and found we had something in common. So he asked if I wanted to get together and watch a fight sometime. I said that would be ok. Anyways he showed up at my house last night to ask if I was going to watch UFC 124. I said yeah and he asked if I mind if he came over and watched it. So he came over. Where I'm going with all this is that I kind of get a cautious vibe about him. I don't know if it's because it seems weird that a person would try and generate a friendship like that or what. I mean it's not like we were introduced by other friends or we met and really hit it off. Anyways it makes me wonder what his intentions are. I'm trying to find out more about his background but everywhere I search online you have to pay for the info. I maybe wrong but I thought public records were free. Does anyone know where to find someones criminal background? Tell me what you think, should I feel wary of this guy?