....forums seem to be rubbish, and anyway, it feels like cheating on the missus to ask questions anywhere else on the net.

I want a BMX, 20" wheel, for larking about at the track, maybe do a few gates and possibly even a few races a bit further down the line.
I used to race loads back in the day and want to get back into it but i've lost touch with current bikes and the like.
How does sizing work on them these days?  If it helps i'm bang on 6 foot tall without any freakishly long or short limbs or anything.
I've looked at manufacturers websites, shop websites and not managed to find anything of any real use.
So anyone got any pointers, please don't tell me to bog off to a BMX forum, they're either frightfully new school with carbon forks and spd's or a bunch of old timers who have a hissy fit if you fit an '83 stem to a '85 bike.

Thats the kind of thing i'm after, cheers.
Okay, i'll start looking at top tube lengths, and as for not being a proper BMX racer, neither will I be! 

you definatley want a longish top tube obviously. Depending on what you get, you might want larger bars. Better for going fast. If you are going to be doing a bit of a racing but dont want a race bike, avoid anything with a sprocket smaller than 30. You will just munch chains and kill rear hubs more often, plus unless you intend to ride loads of park or street aswell you dont need it.

any ideas on budget? you can get some fairly light, cheapish trail style completes nowadays. then whack a v brake lever on it. that might be best rather than buying a carbon speed machine that wont be any use anywhere but the track.