Here is my Dawes Galaxy fixed gear conversion which I built up recently after finally gathering all the bits and dealing with chainline agonies!
Used a Sugino 103mm bottom bracket with Stronlight 165mm track crank. Unfortunately, had to place the chainring on the inside of the spider to get the right chainline which niggles me but had to be done. Chain is a 3/32 SRAM PC58, 44 tooth stronglight chainring and Phil Wood 16T sprocket on the hub. Fixed/free Formula hub on the back but have no tried with a freewheel as yet. Harris Cyclery (Sheldon Brown's shop) on the front - pretty cheap but seems OK so far. I am heavy so rims are Mavic 36 hole A719'S - had wheels built up at Condor Cycles in London. Frame is a 1980's Dawes Galaxy 21" lugged steel 531 frame - nice and comfortable. Brooks Swift saddle which is finally breaking in after 1500 miles.
I have two set-ups, rather ugly/heavy looking set up for daily commute from N.E. London to central London in the winter months with front/rear brakes. Summer set up with just front Goldfinger lever and one Alhonga, deep drop, dual pivot, brake - the only brakes I could find to cope with 700c wheels on an frame designed for 27" wheels. Rides really nicely. Great gallery and website.