Hi- just wondered if anyone out there can give me some advice?

Been out of Road riding for some years now (20 to be precise), & recently sold my old 80's road frame - I felt a little precarious on it these days, but as I'd like to get back into it (I say this every year after the Tour, or when I go to watch the classics in Belgium, but this year I am determined, & MTB 'aint proper cycling' no matter what they say!) figured I'd get one of the newer type sloping top tube ones to replace it - probably psychological, but they just look lower to the ground!

I've purchased a 2010 Specialized Secteur frame, but with no forks or headset, & as I'm a bit out of touch with bicycle mechanics, I wondered what size fork I'd need - diameter - Is it 1 1/8th, or bigger than that? Also, it has a fully integrated headset (I think that's what it is anyway) - Is there a special type I need, like an own brand one, or will any fit it? The races (I assume that's what they are) are still in the headtube of the frame - Are they a fixed thing, or the remnant of the original headset, & do I need to remove them?

Thanks a lot - Paul