what do i do ?

Oh brother what a kettle of worms. Mate if you have been MTBing i would guess that you have a LBS that you trust. Get in there and talk to them about the bikes they deal with, ride them.See what works for you. Your weight and hieght the amount of ks and purpose of the bike all come into play.

Would suggest that in that price range you will be buying complete bike rather than doing a build (have just done one myself and it would have done my head in, if not for the help of trusted LBS).Really i think that it will boil down to you finding a shop that you feel you can trust and putting your butt in to as many saddles as you can.

Cheers enjoy. Don't be in any hurry.

3k seems a bit high for just getting into road cycling, you could spend 1500 and find a very nice bike and save yourself some money - just a suggestion.

I echo the above response, go to every LBS around and try out all the bikes in your price range and go with the bike that feels the best for you. I tend to believe you should buy more for the frame, meaning I'd rather spend my money on a really nice frame with ok components (they can be upgraded), rather than an ok frame with really nice components - that's just my philosophy.