get a tatty old one off ebay with a steel frame from the 80's. make sure its got decent wheels, everything else is replaceable quite cheap off the bay (so long as you don't chase modern kit. I got….
Peugeot performance 2000 bike with reynolds tube (just the downtube I think), straight rigida wheels and brand new tyres, 105 brake levers. £75
then added…
Dura ace rear mech £15
Dura ace front mech £5
Dura ace shifters £22
new chain £12
New grip tape £4
New cables all round £20
Top notch for less than £200.
admitably its a bit retro (and isn't working at the moment due to my dodgy building skills), but bargains can be had if you're carefull…
http://cgi.ebay.co.uk/Raleigh-Dyna-Tech-600-Road-Bike_W0QQitemZ270431579225QQcmdZViewItemQQptZUK_Bikes_GL?hash=item3ef6fa6c59&_trksid=p3286.c0.m14&_trkparms=65%3A7%7C66%3A2%7C39%3A1%7C293%3A1%7C294%3A50
its the right size, its cheap as chips, its in wakey (You're yorkshire aren't you?) and with a respray it could be quite nice…