No reads on the table, but it's WPX, and they all seem pretty tight for the most part... We each have about $100 to start the hand...

Villan raises to $3 in MP... I reraise to $11 w/ ... He's the only caller..

Flop (pot about $25) ... He checks, I bet $21, he calls fairly quickly...

Turn (pot ~$67) ... He checks... What's your play??? If I bet the turn, I'm gonna be in too deep if he has a bigger pair or a set... Do you check behind and pray an overcard doesn't come...???

Why are you bothering about an overcard? If the villian is tight he has a PP here. So you are ahead of JJ, TT and behind to AA, KK, 99, 88, 22. I doubt that he would float you OOP with a small PP. If he had AA, KK he would likely raise you on flop, so I think you should mostly fear a slowplayed set or you are ahead of JJ, TT.

I think I would check turn here without a read and probably would call about a half pot bet on the river if A, or K doesn't come (If A or K comes and he bets it would mean that he can beat AK, so QQ is no good). If river is a small blank and he checks I would value bet aginsy his JJ, TT.

I think he has KK here, but is fearing AA, poss JJ, TT but he should have raised your flop bet. I would check and value bet if he checks on the river, providing no high card on the river.

If he raises me on the flop, easy fold??? I'm figuring he's prolly gonna raise JJ and possibly TT just as often as AA or KK..

Your PF reraise must say AA/KK/QQ/AK to him, and lacking a read you have to assume he's a standard player for the site and raises PF more often with AA/KK from MP than with JJ/TT. Therefore, if he raises the flop I'd fold.

I'd check the turn and call up to about $30 on the river, which represents about how often I expect to win/lose.

I would check behind there most of the time and call a reasonable bet on the river or valuebet it myself if checked to.